[alsa-devel] Sound to HDMI device delayed

[Takashi Iwai]

On Tue, 26 Dec 2017 15:32:21 +0100,
Freek de Kruijf wrote:
> 
> I have the following sound devices:
> 
> hwinfo --sound          
> Absolute path to 'hwinfo' is '/usr/sbin/hwinfo', so running it may require 
> superuser privileges (eg. root).
> freek at eiktum:~> /usr/sbin/hwinfo --sound 
> 16: PCI 14.2: 0403 Audio device                                 
>   [Created at pci.378]
>   Unique ID: 5Dex.BDUuYMOWyw7
>   SysFS ID: /devices/pci0000:00/0000:00:14.2
>   SysFS BusID: 0000:00:14.2
>   Hardware Class: sound
>   Model: "ATI SBx00 Azalia (Intel HDA)"
>   Vendor: pci 0x1002 "ATI Technologies Inc"
>   Device: pci 0x4383 "SBx00 Azalia (Intel HDA)"
>   SubVendor: pci 0x1002 "ATI Technologies Inc"
>   SubDevice: pci 0x4383 
>   Revision: 0x40
>   Memory Range: 0xfe6f8000-0xfe6fbfff (rw,non-prefetchable)
>   IRQ: 10 (no events)
>   Module Alias: "pci:v00001002d00004383sv00001002sd00004383bc04sc03i00"
>   Driver Info #0:
>     Driver Status: snd_hda_intel is active
>     Driver Activation Cmd: "modprobe snd_hda_intel"
>   Config Status: cfg=yes, avail=yes, need=no, active=unknown
> 
> 26: PCI 500.1: 0403 Audio device
>   [Created at pci.378]
>   Unique ID: 5yAR.dhjYDcGDBr3
>   Parent ID: _Znp.ZJmKoWxd6BF
>   SysFS ID: /devices/pci0000:00/0000:00:02.0/0000:05:00.1
>   SysFS BusID: 0000:05:00.1
>   Hardware Class: sound
>   Model: "ATI RV770 HDMI Audio [Radeon HD 4850/4870]"
>   Vendor: pci 0x1002 "ATI Technologies Inc"
>   Device: pci 0xaa30 "RV770 HDMI Audio [Radeon HD 4850/4870]"
>   SubVendor: pci 0x1787 "Hightech Information System Ltd."
>   SubDevice: pci 0xaa30 
>   Driver: "snd_hda_intel"
>   Driver Modules: "snd_hda_intel"
>   Memory Range: 0xfe9ec000-0xfe9effff (rw,non-prefetchable)
>   IRQ: 36 (1104 events)
>   Module Alias: "pci:v00001002d0000AA30sv00001787sd0000AA30bc04sc03i00"
>   Driver Info #0:
>     Driver Status: snd_hda_intel is active
>     Driver Activation Cmd: "modprobe snd_hda_intel"
>   Config Status: cfg=yes, avail=yes, need=no, active=unknown
>   Attached to: #18 (PCI bridge)
> 
> I have my monitor connected via HDMI and that monitor has speakers. The 
> monitor is:
> 
> hwinfo --monitor
> 29: None 00.0: 10002 LCD Monitor                                
>   [Created at monitor.125]
>   Unique ID: rdCR.ukgc1_4VzS0
>   Parent ID: Ddhb.zvQlrOmSRQ8
>   Hardware Class: monitor
>   Model: "R231"
>   Vendor: ACR 
>   Device: eisa 0x0504 "R231"
>   Serial ID: "T6GEE0012400"
>   Resolution: 720x400 at 70Hz
>   Resolution: 640x480 at 60Hz
>   Resolution: 640x480 at 67Hz
>   Resolution: 800x600 at 56Hz
>   Resolution: 800x600 at 60Hz
>   Resolution: 1024x768 at 60Hz
>   Resolution: 1024x768 at 70Hz
>   Resolution: 1152x864 at 75Hz
>   Resolution: 1280x1024 at 60Hz
>   Resolution: 1280x720 at 60Hz
>   Resolution: 1920x1080 at 60Hz
>   Size: 509x286 mm
>   Year of Manufacture: 2016
>   Week of Manufacture: 4
>   Detailed Timings #0:
>      Resolution: 1920x1080
>      Horizontal: 1920 2008 2052 2200 (+88 +132 +280) +hsync
>        Vertical: 1080 1084 1089 1125 (+4 +9 +45) +vsync
>     Frequencies: 148.50 MHz, 67.50 kHz, 60.00 Hz
>   Driver Info #0:
>     Max. Resolution: 1920x1080
>     Vert. Sync Range: 56-75 Hz
>     Hor. Sync Range: 31-75 kHz
>     Bandwidth: 148 MHz
>   Config Status: cfg=no, avail=yes, need=no, active=unknown
>   Attached to: #8 (VGA compatible controller)
> 
> The sound is working OK, however the problem is that the sound is delayed by 
> about one second compared to the picture on the screen.
> Most visible/hearable by using Musescore, where a music note is highlighted 
> when it is played. Using VGA and the other sound card there is no delay.

I don't know of such a problem, and I can't think that such a long
delay happens in the hardware side.

Which sound backend are you using?  Does the same delay happen even if
you play directly via aplay with -Dplughw?


Takashi