[alsa-devel] Bug report: [alsa-sink-USB Audio] alsa-sink.c: Most likely this is a bug in the ALSA driver '(null)'. Please report this issue to the ALSA

[Justin Piszcz]

On Sat, May 31, 2014 at 12:58 AM, Raymond Yau
<superquad.vortex2 at gmail.com> wrote:
>
>>
>>
>>
>> As requested—
>>
>>
>>
>> http://home.comcast.net/~jpiszcz/20140530/lsusb-vvvv.txt
>>
>> http://home.comcast.net/~jpiszcz/20140530/full-pulse-audio-log.txt
>
>>
>> http://home.comcast.net/~jpiszcz/20140530/alsa-info.txt
>>
>
> control.6 {
> iface MIXER
> name 'Speaker Playback Volume'
> value.0 151
> value.1 151
> comment {
> access 'read write'
> type INTEGER
> count 2
> range '0 - 151'
> dbmin -2837
> dbmax -6
> dbvalue.0 -6
> dbvalue.1 -6
> }
> }
>
> You have to specify log_info=debug in daemon.conf
>
> Check the pulseaudio debug log whether pulseaudio calculated  software
> volume is accurate enough (VOLUME_ACCURACY=PA_VOLUME_NORM/100) since your
> Max dB  -0.06 are quite close to PA_VOLUME_NORM
>
>>
>>
>> Ø  step to reproduce your problem when you report the bug
>
>>
>> I often SSH to my machine or use X remotely and not locally— this is the
>> first time I have seen this in logs that I can remember and I’ve not changed
>> anything locally.
>>
>
>> > ==> /var/log/user.log <==
>> >
>> > May 25 06:38:06 atom pulseaudio[6754]: [alsa-sink-USB Audio]
>> > alsa-sink.c:
>> > ALSA woke us up to write new data to the device, but there was actually
>> > nothing to write!
>> >
>> > May 25 06:38:06 atom pulseaudio[6754]: [alsa-sink-USB Audio]
>> > alsa-sink.c:
>> > Most likely this is a bug in the ALSA driver '(null)'. Please report
>> > this
>> > issue to the ALSA developers.
>>
>> Name of alsa sink seem changed from USB-audio to null,  did you find any
>> unplug event if USB audio device in system log
>>
>> Any error message related to USB controllers and your audio card
>>
>> >
>> > May 25 06:38:06 atom pulseaudio[6754]: [alsa-sink-USB Audio]
>> > alsa-sink.c: We
>> > were woken up with POLLOUT set -- however a subsequent snd_pcm_avail()
>> > returned 0 or another value < min_avail.
>> >
>> >
>
> http://www.alsa-project.org/main/index.php/XRUN_Debug
>
> /proc/asound/card#/pcm0p/xrun_debug
>
> Replace '#' with your card number (usually 0). This proc file can enable
> various debugging tools. The CONFIG_SND_PCM_XRUN_DEBUG,
> CONFIG_SND_VERBOSE_PROCFS, CONFIG_SND_DEBUG options must be enabled in your
> kernel (if xrun_debug proc file is present - this feature is enabled).
>
> # Enable basic debugging and dump stack, check hardware pointer on the
> period update
> # Usefull to just see, if PCM stream is stopped for a reason (usually wrong
> audio process timing from scheduler)
> # And to check the values from driver
> echo 11 > /proc/asound/card0/pcm0p/xrun_debug

Thanks, if I can reproduce it- I will try this, so far I have not been
able to get it to recur.

Regards,

Justin.