I am using Takashi Iwai's tree grafted onto mainline as DKMS ( as in https://github.com/HinTak/sound-usb-dkms ).
Running the alsa compliance test commit f6167eb77d038b5b7a0d39645e7f2ae7fee6fdc0 (origin/stabilize-12464.B, origin/release-R78-12499.B)
Capture all passed, but play back failed a couple, regarding the sample rate. It is a small head set with stereo head phone and a mic. ID 046d:0a38 Logitech, Inc. Headset H340
The question is, for such a cheap headset, why would the playback rate and the capture rate to be different? For many applications/ usages, with a device that's most capture and playback capable, we would like the rates to agree - both pass, or both fail in the same direction?
Is this a hardware or software issue? Or, somebody suggested, I haven't looked, issue with the alsa compliance test itself, possibly regarding frame counts of usb devices?
detail below.
5 passed, 0 failed Device Information Name: hw:CARD=H340 Stream: CAPTURE Format: ['S16_LE'] Channels range: [2, 2] Rate: [44100] Period_size range: [45, 131072] Buffer_size range: [90, 262144] Test Params Set channels 2: pass Set format S16_LE: pass Set rate 44100: pass Test Rates Set rate 44100: pass Test All Pairs Set channels 2, format S16_LE, rate 44100: pass
3 passed, 2 failed Device Information Name: hw:CARD=H340 Stream: PLAYBACK Format: ['S16_LE'] Channels range: [2, 2] Rate: [44100] Period_size range: [45, 131072] Buffer_size range: [90, 262144] Test Params Set channels 2: pass Set format S16_LE: pass Set rate 44100: pass Test Rates Set rate 44100: fail - Expected rate is 44100.000000, measure 44092.918362, difference 7.081638 > threshold 4.410000 Test All Pairs Set channels 2, format S16_LE, rate 44100: fail - Expected rate is 44100.000000, measure 44093.049192, difference 6.950808 > threshold 4.410000