Ignored USB-audio implicit feedback in kernel 5.8rc3

Pavel Hofman pavel.hofman at ivitera.com
Mon Jun 29 13:28:46 CEST 2020


Hi,

Audio analyzer RTX6001 (XMOS-based) is using implicit feedback, yet the 
feedback is not used by the latest kernel 5.8 rc3 (i.e. already with the 
latest implicit-feedback patches).

Two analyzers on two different PCs are getting clicks in duplex-mode 
loobpack, one every 10 secs, the other one every 50 secs.

While running aplay/arecord loopback I captured USB packets with 
tcpdump/tshark. The dump contained 931484 IN packets with 48bytes 
payload, and 684 IN  packets with 40 bytes payload. Packet interval 
125us (bInterval = 1), 32bits, 2ch => precise samplerate 47,994.1298Hz. 
Clearly the incoming stream works OK. Yet stream0 file states for Capture:

Momentary freq = 48000 Hz (0x6.0000)

But ONLY 48bytes packets were sent by the host in OUT packets, i.e. 
exactly 48kHz output rate. 6 frames OUT/IN difference per second, the 
incoming FIFO in the device overflows after several seconds.

Please may I ask for help with making the driver respect the implicit 
feedback stream?

Best regards,

Pavel.


5.8.0-050800-generic #202006282330 SMP Sun Jun 28 23:35:41 UTC 2020 
x86_64 GNU/Linux


cat /proc/asound/card4/stream0
RTX A/S RTX6001 USB Audio 2.0 at usb-0000:00:13.2-4, high speed : USB Audio

Playback:
Status: Running
Interface = 1
Altset = 1
Packet Size = 72
Momentary freq = 48000 Hz (0x6.0000)
Interface 1
Altset 1
Format: S32_LE
Channels: 2
Endpoint: 1 OUT (ASYNC)
Rates: 44100, 48000, 88200, 96000, 176400, 192000
Data packet interval: 125 us
Bits: 32
Channel map: FL FR
Interface 1
Altset 2
Format: S32_LE
Channels: 2
Endpoint: 1 OUT (ASYNC)
Rates: 44100, 48000, 88200, 96000, 176400, 192000
Data packet interval: 125 us
Bits: 24
Channel map: FL FR
Interface 1
Altset 3
Format: S16_LE
Channels: 2
Endpoint: 1 OUT (ASYNC)
Rates: 44100, 48000, 88200, 96000, 176400, 192000
Data packet interval: 125 us
Bits: 16
Channel map: FL FR

Capture:
Status: Stop
Interface 2
Altset 1
Format: S32_LE
Channels: 2
Endpoint: 1 IN (ASYNC)
Rates: 44100, 48000, 88200, 96000, 176400, 192000
Data packet interval: 125 us
Bits: 32
Channel map: FL FR
Interface 2
Altset 2
Format: S32_LE
Channels: 2
Endpoint: 1 IN (ASYNC)
Rates: 44100, 48000, 88200, 96000, 176400, 192000
Data packet interval: 125 us
Bits: 24
Channel map: FL FR
Interface 2
Altset 3
Format: S16_LE
Channels: 2
Endpoint: 1 IN (ASYNC)
Rates: 44100, 48000, 88200, 96000, 176400, 192000
Data packet interval: 125 us
Bits: 16
Channel map: FL FR


lsusb:
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 007 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 002: ID 058f:6362 Alcor Micro Corp. Flash Card Reader/Writer
Bus 002 Device 003: ID 0d9a:00df RTX AS RTX6001 USB Audio 2.0    <----
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 008: ID 2047:0301 Texas Instruments Arduino Micro
Bus 004 Device 007: ID 18f8:0f97 [Maxxter] Elo TouchSystems 2216 
AccuTouch® USB Touchmonitor Interface
Bus 004 Device 006: ID 413c:2001 Dell Computer Corp. Keyboard HID Support
Bus 004 Device 005: ID 413c:1001 Dell Computer Corp. Keyboard Hub
Bus 004 Device 004: ID 0bd9:0001 Liberty Instruments, Inc. Liberty 
Praxis AudPod 1.1
Bus 004 Device 003: ID 2341:8037 Arduino SA Arduino Micro
Bus 004 Device 002: ID 04e7:0050 Elo TouchSystems 2216 AccuTouch® 
Touchmonitor Interface
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 009 Device 002: ID 18a5:0422 Verbatim, Ltd Portable SSD
Bus 009 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 008 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

lsusb -v see the attachment
-------------- next part --------------

Bus 002 Device 003: ID 0d9a:00df RTX AS RTX6001 USB Audio 2.0
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass          239 Miscellaneous Device
  bDeviceSubClass         2 
  bDeviceProtocol         1 Interface Association
  bMaxPacketSize0        64
  idVendor           0x0d9a RTX AS
  idProduct          0x00df 
  bcdDevice            1.19
  iManufacturer           1 
  iProduct                3 
  iSerial                 2 
  bNumConfigurations      2
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x01c5
    bNumInterfaces          5
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xc0
      Self Powered
    MaxPower                0mA
    Interface Association:
      bLength                 8
      bDescriptorType        11
      bFirstInterface         0
      bInterfaceCount         3
      bFunctionClass          1 Audio
      bFunctionSubClass       0 
      bFunctionProtocol      32 
      iFunction               0 
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           0
      bInterfaceClass         1 Audio
      bInterfaceSubClass      1 Control Device
      bInterfaceProtocol     32 
      iInterface              3 
      AudioControl Interface Descriptor:
        bLength                 9
        bDescriptorType        36
        bDescriptorSubtype      1 (HEADER)
        bcdADC               2.00
        bCategory               8
        wTotalLength       0x0053
        bmControls           0x00
      AudioControl Interface Descriptor:
        bLength                 8
        bDescriptorType        36
        bDescriptorSubtype     10 (CLOCK_SOURCE)
        bClockID               41
        bmAttributes            3 Internal programmable clock 
        bmControls           0x07
          Clock Frequency Control (read/write)
          Clock Validity Control (read-only)
        bAssocTerminal          0
        iClockSource            9 
      AudioControl Interface Descriptor:
        bLength                 8
        bDescriptorType        36
        bDescriptorSubtype     11 (CLOCK_SELECTOR)
        bClockID               40
        bNrInPins               1
        baCSourceID(0)         41
        bmControls           0x03
          Clock Selector Control (read/write)
        iClockSelector          8 
      AudioControl Interface Descriptor:
        bLength                17
        bDescriptorType        36
        bDescriptorSubtype      2 (INPUT_TERMINAL)
        bTerminalID             2
        wTerminalType      0x0101 USB Streaming
        bAssocTerminal          0
        bCSourceID             40
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          11 
        bmControls         0x0000
        iTerminal               6 
      AudioControl Interface Descriptor:
        bLength                12
        bDescriptorType        36
        bDescriptorSubtype      3 (OUTPUT_TERMINAL)
        bTerminalID            20
        wTerminalType      0x0301 Speaker
        bAssocTerminal          0
        bSourceID               2
        bCSourceID             40
        bmControls         0x0000
        iTerminal               0 
      AudioControl Interface Descriptor:
        bLength                17
        bDescriptorType        36
        bDescriptorSubtype      2 (INPUT_TERMINAL)
        bTerminalID             1
        wTerminalType      0x0201 Microphone
        bAssocTerminal          0
        bCSourceID             40
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          13 
        bmControls         0x0000
        iTerminal               0 
      AudioControl Interface Descriptor:
        bLength                12
        bDescriptorType        36
        bDescriptorSubtype      3 (OUTPUT_TERMINAL)
        bTerminalID            22
        wTerminalType      0x0101 USB Streaming
        bAssocTerminal          0
        bSourceID               2
        bCSourceID             40
        bmControls         0x0000
        iTerminal               7 
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       0
      bNumEndpoints           0
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              4 
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       1
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              4 
      AudioStreaming Interface Descriptor:
        bLength                16
        bDescriptorType        36
        bDescriptorSubtype      1 (AS_GENERAL)
        bTerminalLink           2
        bmControls           0x00
        bFormatType             1
        bmFormats          0x00000001
          PCM
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          11 
      AudioStreaming Interface Descriptor:
        bLength                 6
        bDescriptorType        36
        bDescriptorSubtype      2 (FORMAT_TYPE)
        bFormatType             1 (FORMAT_TYPE_I)
        bSubslotSize            4
        bBitResolution         32
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x01  EP 1 OUT
        bmAttributes            5
          Transfer Type            Isochronous
          Synch Type               Asynchronous
          Usage Type               Data
        wMaxPacketSize     0x0308  1x 776 bytes
        bInterval               1
        AudioStreaming Endpoint Descriptor:
          bLength                 8
          bDescriptorType        37
          bDescriptorSubtype      1 (EP_GENERAL)
          bmAttributes         0x00
          bmControls           0x00
          bLockDelayUnits         2 Decoded PCM samples
          wLockDelay         0x0008
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       2
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              4 
      AudioStreaming Interface Descriptor:
        bLength                16
        bDescriptorType        36
        bDescriptorSubtype      1 (AS_GENERAL)
        bTerminalLink           2
        bmControls           0x00
        bFormatType             1
        bmFormats          0x00000001
          PCM
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          11 
      AudioStreaming Interface Descriptor:
        bLength                 6
        bDescriptorType        36
        bDescriptorSubtype      2 (FORMAT_TYPE)
        bFormatType             1 (FORMAT_TYPE_I)
        bSubslotSize            4
        bBitResolution         24
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x01  EP 1 OUT
        bmAttributes            5
          Transfer Type            Isochronous
          Synch Type               Asynchronous
          Usage Type               Data
        wMaxPacketSize     0x0308  1x 776 bytes
        bInterval               1
        AudioStreaming Endpoint Descriptor:
          bLength                 8
          bDescriptorType        37
          bDescriptorSubtype      1 (EP_GENERAL)
          bmAttributes         0x00
          bmControls           0x00
          bLockDelayUnits         2 Decoded PCM samples
          wLockDelay         0x0008
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       3
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              4 
      AudioStreaming Interface Descriptor:
        bLength                16
        bDescriptorType        36
        bDescriptorSubtype      1 (AS_GENERAL)
        bTerminalLink           2
        bmControls           0x00
        bFormatType             1
        bmFormats          0x00000001
          PCM
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          11 
      AudioStreaming Interface Descriptor:
        bLength                 6
        bDescriptorType        36
        bDescriptorSubtype      2 (FORMAT_TYPE)
        bFormatType             1 (FORMAT_TYPE_I)
        bSubslotSize            2
        bBitResolution         16
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x01  EP 1 OUT
        bmAttributes            5
          Transfer Type            Isochronous
          Synch Type               Asynchronous
          Usage Type               Data
        wMaxPacketSize     0x0184  1x 388 bytes
        bInterval               1
        AudioStreaming Endpoint Descriptor:
          bLength                 8
          bDescriptorType        37
          bDescriptorSubtype      1 (EP_GENERAL)
          bmAttributes         0x00
          bmControls           0x00
          bLockDelayUnits         2 Decoded PCM samples
          wLockDelay         0x0008
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        2
      bAlternateSetting       0
      bNumEndpoints           0
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              5 
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        2
      bAlternateSetting       1
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              5 
      AudioStreaming Interface Descriptor:
        bLength                16
        bDescriptorType        36
        bDescriptorSubtype      1 (AS_GENERAL)
        bTerminalLink          22
        bmControls           0x00
        bFormatType             1
        bmFormats          0x00000001
          PCM
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          13 
      AudioStreaming Interface Descriptor:
        bLength                 6
        bDescriptorType        36
        bDescriptorSubtype      2 (FORMAT_TYPE)
        bFormatType             1 (FORMAT_TYPE_I)
        bSubslotSize            4
        bBitResolution         32
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes           37
          Transfer Type            Isochronous
          Synch Type               Asynchronous
          Usage Type               Implicit feedback Data
        wMaxPacketSize     0x0308  1x 776 bytes
        bInterval               1
        AudioStreaming Endpoint Descriptor:
          bLength                 8
          bDescriptorType        37
          bDescriptorSubtype      1 (EP_GENERAL)
          bmAttributes         0x00
          bmControls           0x00
          bLockDelayUnits         2 Decoded PCM samples
          wLockDelay         0x0008
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        2
      bAlternateSetting       2
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              5 
      AudioStreaming Interface Descriptor:
        bLength                16
        bDescriptorType        36
        bDescriptorSubtype      1 (AS_GENERAL)
        bTerminalLink          22
        bmControls           0x00
        bFormatType             1
        bmFormats          0x00000001
          PCM
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          13 
      AudioStreaming Interface Descriptor:
        bLength                 6
        bDescriptorType        36
        bDescriptorSubtype      2 (FORMAT_TYPE)
        bFormatType             1 (FORMAT_TYPE_I)
        bSubslotSize            4
        bBitResolution         24
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes           37
          Transfer Type            Isochronous
          Synch Type               Asynchronous
          Usage Type               Implicit feedback Data
        wMaxPacketSize     0x0308  1x 776 bytes
        bInterval               1
        AudioStreaming Endpoint Descriptor:
          bLength                 8
          bDescriptorType        37
          bDescriptorSubtype      1 (EP_GENERAL)
          bmAttributes         0x00
          bmControls           0x00
          bLockDelayUnits         2 Decoded PCM samples
          wLockDelay         0x0008
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        2
      bAlternateSetting       3
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              5 
      AudioStreaming Interface Descriptor:
        bLength                16
        bDescriptorType        36
        bDescriptorSubtype      1 (AS_GENERAL)
        bTerminalLink          22
        bmControls           0x00
        bFormatType             1
        bmFormats          0x00000001
          PCM
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          13 
      AudioStreaming Interface Descriptor:
        bLength                 6
        bDescriptorType        36
        bDescriptorSubtype      2 (FORMAT_TYPE)
        bFormatType             1 (FORMAT_TYPE_I)
        bSubslotSize            2
        bBitResolution         16
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes           37
          Transfer Type            Isochronous
          Synch Type               Asynchronous
          Usage Type               Implicit feedback Data
        wMaxPacketSize     0x0308  1x 776 bytes
        bInterval               1
        AudioStreaming Endpoint Descriptor:
          bLength                 8
          bDescriptorType        37
          bDescriptorSubtype      1 (EP_GENERAL)
          bmAttributes         0x00
          bmControls           0x00
          bLockDelayUnits         2 Decoded PCM samples
          wLockDelay         0x0008
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        3
      bAlternateSetting       0
      bNumEndpoints           0
      bInterfaceClass       254 Application Specific Interface
      bInterfaceSubClass      1 Device Firmware Update
      bInterfaceProtocol      1 
      iInterface             10 
      Device Firmware Upgrade Interface Descriptor:
        bLength                             9
        bDescriptorType                    33
        bmAttributes                        7
          Will Not Detach
          Manifestation Tolerant
          Upload Supported
          Download Supported
        wDetachTimeout                    250 milliseconds
        wTransferSize                      64 bytes
        bcdDFUVersion                   1.10
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        4
      bAlternateSetting       0
      bNumEndpoints           2
      bInterfaceClass         3 Human Interface Device
      bInterfaceSubClass      0 
      bInterfaceProtocol      0 
      iInterface              0 
        HID Device Descriptor:
          bLength                 9
          bDescriptorType        33
          bcdHID               1.10
          bCountryCode            0 Not supported
          bNumDescriptors         1
          bDescriptorType        34 Report
          wDescriptorLength     202
         Report Descriptors: 
           ** UNAVAILABLE **
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x02  EP 2 OUT
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval               8
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x82  EP 2 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval               8
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x01c5
    bNumInterfaces          5
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xc0
      Self Powered
    MaxPower                0mA
    Interface Association:
      bLength                 8
      bDescriptorType        11
      bFirstInterface         0
      bInterfaceCount         3
      bFunctionClass          1 Audio
      bFunctionSubClass       0 
      bFunctionProtocol      32 
      iFunction               0 
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           0
      bInterfaceClass         1 Audio
      bInterfaceSubClass      1 Control Device
      bInterfaceProtocol     32 
      iInterface              3 
      AudioControl Interface Descriptor:
        bLength                 9
        bDescriptorType        36
        bDescriptorSubtype      1 (HEADER)
        bcdADC               2.00
        bCategory               8
        wTotalLength       0x0053
        bmControls           0x00
      AudioControl Interface Descriptor:
        bLength                 8
        bDescriptorType        36
        bDescriptorSubtype     10 (CLOCK_SOURCE)
        bClockID               41
        bmAttributes            3 Internal programmable clock 
        bmControls           0x07
          Clock Frequency Control (read/write)
          Clock Validity Control (read-only)
        bAssocTerminal          0
        iClockSource            9 
      AudioControl Interface Descriptor:
        bLength                 8
        bDescriptorType        36
        bDescriptorSubtype     11 (CLOCK_SELECTOR)
        bClockID               40
        bNrInPins               1
        baCSourceID(0)         41
        bmControls           0x03
          Clock Selector Control (read/write)
        iClockSelector          8 
      AudioControl Interface Descriptor:
        bLength                17
        bDescriptorType        36
        bDescriptorSubtype      2 (INPUT_TERMINAL)
        bTerminalID             2
        wTerminalType      0x0101 USB Streaming
        bAssocTerminal          0
        bCSourceID             40
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          11 
        bmControls         0x0000
        iTerminal               6 
      AudioControl Interface Descriptor:
        bLength                12
        bDescriptorType        36
        bDescriptorSubtype      3 (OUTPUT_TERMINAL)
        bTerminalID            20
        wTerminalType      0x0301 Speaker
        bAssocTerminal          0
        bSourceID               2
        bCSourceID             40
        bmControls         0x0000
        iTerminal               0 
      AudioControl Interface Descriptor:
        bLength                17
        bDescriptorType        36
        bDescriptorSubtype      2 (INPUT_TERMINAL)
        bTerminalID             1
        wTerminalType      0x0201 Microphone
        bAssocTerminal          0
        bCSourceID             40
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          13 
        bmControls         0x0000
        iTerminal               0 
      AudioControl Interface Descriptor:
        bLength                12
        bDescriptorType        36
        bDescriptorSubtype      3 (OUTPUT_TERMINAL)
        bTerminalID            22
        wTerminalType      0x0101 USB Streaming
        bAssocTerminal          0
        bSourceID               2
        bCSourceID             40
        bmControls         0x0000
        iTerminal               7 
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       0
      bNumEndpoints           0
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              4 
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       1
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              4 
      AudioStreaming Interface Descriptor:
        bLength                16
        bDescriptorType        36
        bDescriptorSubtype      1 (AS_GENERAL)
        bTerminalLink           2
        bmControls           0x00
        bFormatType             1
        bmFormats          0x00000001
          PCM
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          11 
      AudioStreaming Interface Descriptor:
        bLength                 6
        bDescriptorType        36
        bDescriptorSubtype      2 (FORMAT_TYPE)
        bFormatType             1 (FORMAT_TYPE_I)
        bSubslotSize            4
        bBitResolution         32
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x01  EP 1 OUT
        bmAttributes            5
          Transfer Type            Isochronous
          Synch Type               Asynchronous
          Usage Type               Data
        wMaxPacketSize     0x0308  1x 776 bytes
        bInterval               1
        AudioStreaming Endpoint Descriptor:
          bLength                 8
          bDescriptorType        37
          bDescriptorSubtype      1 (EP_GENERAL)
          bmAttributes         0x00
          bmControls           0x00
          bLockDelayUnits         2 Decoded PCM samples
          wLockDelay         0x0008
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       2
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              4 
      AudioStreaming Interface Descriptor:
        bLength                16
        bDescriptorType        36
        bDescriptorSubtype      1 (AS_GENERAL)
        bTerminalLink           2
        bmControls           0x00
        bFormatType             1
        bmFormats          0x00000001
          PCM
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          11 
      AudioStreaming Interface Descriptor:
        bLength                 6
        bDescriptorType        36
        bDescriptorSubtype      2 (FORMAT_TYPE)
        bFormatType             1 (FORMAT_TYPE_I)
        bSubslotSize            4
        bBitResolution         24
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x01  EP 1 OUT
        bmAttributes            5
          Transfer Type            Isochronous
          Synch Type               Asynchronous
          Usage Type               Data
        wMaxPacketSize     0x0308  1x 776 bytes
        bInterval               1
        AudioStreaming Endpoint Descriptor:
          bLength                 8
          bDescriptorType        37
          bDescriptorSubtype      1 (EP_GENERAL)
          bmAttributes         0x00
          bmControls           0x00
          bLockDelayUnits         2 Decoded PCM samples
          wLockDelay         0x0008
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       3
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              4 
      AudioStreaming Interface Descriptor:
        bLength                16
        bDescriptorType        36
        bDescriptorSubtype      1 (AS_GENERAL)
        bTerminalLink           2
        bmControls           0x00
        bFormatType             1
        bmFormats          0x00000001
          PCM
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          11 
      AudioStreaming Interface Descriptor:
        bLength                 6
        bDescriptorType        36
        bDescriptorSubtype      2 (FORMAT_TYPE)
        bFormatType             1 (FORMAT_TYPE_I)
        bSubslotSize            2
        bBitResolution         16
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x01  EP 1 OUT
        bmAttributes            5
          Transfer Type            Isochronous
          Synch Type               Asynchronous
          Usage Type               Data
        wMaxPacketSize     0x0184  1x 388 bytes
        bInterval               1
        AudioStreaming Endpoint Descriptor:
          bLength                 8
          bDescriptorType        37
          bDescriptorSubtype      1 (EP_GENERAL)
          bmAttributes         0x00
          bmControls           0x00
          bLockDelayUnits         2 Decoded PCM samples
          wLockDelay         0x0008
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        2
      bAlternateSetting       0
      bNumEndpoints           0
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              5 
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        2
      bAlternateSetting       1
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              5 
      AudioStreaming Interface Descriptor:
        bLength                16
        bDescriptorType        36
        bDescriptorSubtype      1 (AS_GENERAL)
        bTerminalLink          22
        bmControls           0x00
        bFormatType             1
        bmFormats          0x00000001
          PCM
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          13 
      AudioStreaming Interface Descriptor:
        bLength                 6
        bDescriptorType        36
        bDescriptorSubtype      2 (FORMAT_TYPE)
        bFormatType             1 (FORMAT_TYPE_I)
        bSubslotSize            4
        bBitResolution         32
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes           37
          Transfer Type            Isochronous
          Synch Type               Asynchronous
          Usage Type               Implicit feedback Data
        wMaxPacketSize     0x0308  1x 776 bytes
        bInterval               1
        AudioStreaming Endpoint Descriptor:
          bLength                 8
          bDescriptorType        37
          bDescriptorSubtype      1 (EP_GENERAL)
          bmAttributes         0x00
          bmControls           0x00
          bLockDelayUnits         2 Decoded PCM samples
          wLockDelay         0x0008
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        2
      bAlternateSetting       2
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              5 
      AudioStreaming Interface Descriptor:
        bLength                16
        bDescriptorType        36
        bDescriptorSubtype      1 (AS_GENERAL)
        bTerminalLink          22
        bmControls           0x00
        bFormatType             1
        bmFormats          0x00000001
          PCM
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          13 
      AudioStreaming Interface Descriptor:
        bLength                 6
        bDescriptorType        36
        bDescriptorSubtype      2 (FORMAT_TYPE)
        bFormatType             1 (FORMAT_TYPE_I)
        bSubslotSize            4
        bBitResolution         24
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes           37
          Transfer Type            Isochronous
          Synch Type               Asynchronous
          Usage Type               Implicit feedback Data
        wMaxPacketSize     0x0308  1x 776 bytes
        bInterval               1
        AudioStreaming Endpoint Descriptor:
          bLength                 8
          bDescriptorType        37
          bDescriptorSubtype      1 (EP_GENERAL)
          bmAttributes         0x00
          bmControls           0x00
          bLockDelayUnits         2 Decoded PCM samples
          wLockDelay         0x0008
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        2
      bAlternateSetting       3
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol     32 
      iInterface              5 
      AudioStreaming Interface Descriptor:
        bLength                16
        bDescriptorType        36
        bDescriptorSubtype      1 (AS_GENERAL)
        bTerminalLink          22
        bmControls           0x00
        bFormatType             1
        bmFormats          0x00000001
          PCM
        bNrChannels             2
        bmChannelConfig    0x00000003
          Front Left (FL)
          Front Right (FR)
        iChannelNames          13 
      AudioStreaming Interface Descriptor:
        bLength                 6
        bDescriptorType        36
        bDescriptorSubtype      2 (FORMAT_TYPE)
        bFormatType             1 (FORMAT_TYPE_I)
        bSubslotSize            2
        bBitResolution         16
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes           37
          Transfer Type            Isochronous
          Synch Type               Asynchronous
          Usage Type               Implicit feedback Data
        wMaxPacketSize     0x0308  1x 776 bytes
        bInterval               1
        AudioStreaming Endpoint Descriptor:
          bLength                 8
          bDescriptorType        37
          bDescriptorSubtype      1 (EP_GENERAL)
          bmAttributes         0x00
          bmControls           0x00
          bLockDelayUnits         2 Decoded PCM samples
          wLockDelay         0x0008
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        3
      bAlternateSetting       0
      bNumEndpoints           0
      bInterfaceClass       254 Application Specific Interface
      bInterfaceSubClass      1 Device Firmware Update
      bInterfaceProtocol      1 
      iInterface             10 
      Device Firmware Upgrade Interface Descriptor:
        bLength                             9
        bDescriptorType                    33
        bmAttributes                        7
          Will Not Detach
          Manifestation Tolerant
          Upload Supported
          Download Supported
        wDetachTimeout                    250 milliseconds
        wTransferSize                      64 bytes
        bcdDFUVersion                   1.10
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        4
      bAlternateSetting       0
      bNumEndpoints           2
      bInterfaceClass         3 Human Interface Device
      bInterfaceSubClass      0 
      bInterfaceProtocol      0 
      iInterface              0 
        HID Device Descriptor:
          bLength                 9
          bDescriptorType        33
          bcdHID               1.10
          bCountryCode            0 Not supported
          bNumDescriptors         1
          bDescriptorType        34 Report
          wDescriptorLength     202
         Report Descriptors: 
           ** UNAVAILABLE **
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x02  EP 2 OUT
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval               8
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x82  EP 2 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval               8


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