[pulseaudio-discuss] USB audio devices muted at non-zero volume

[David Henningsson]

On 2011-01-06 15:31, Colin Guthrie wrote:
> Hi Marius
>
> 'Twas brillig, and Marius Bjørnstad at 06/01/11 12:39 did gyre and gimble:
>> The devices below are muted at a volume greater than 0. This causes a
>> significant portion of the volume in Pulseaudio to be equal to zero (muted).
>>
>> 0d8c:000e C-Media Electronics, Inc. Audio Adapter (Planet UP-100, Genius
>> G-Talk)
>>
>> 0b05:1743 ASUSTek Computer, Inc. Xonar U1 Audio Station
>>
>> The asus card is muted at volume "1",
>> the Plantronics ( C-Media ) is muted at volume "2". Both volumes are in
>> alsamixer.
>>
>> Is there any way to fix this in Pulseaudio (some kind of "quirks"
>> database, for example)?
>
> This isn't an uncommon thing, but it's getting better.
>
> The problem is very likely that the device is incorrectly reporting it's
> dB range and thus PA cannot control it correctly. It's possible to add
> quirks in the driver to correct the range.
>
> http://www.pulseaudio.org/wiki/BadDecibel
> http://mailman.alsa-project.org/pipermail/alsa-devel/2010-February/025213.html
>
> David Henningsson from Canonical also wrote a similar tool:
> http://thread.gmane.org/gmane.comp.audio.pulseaudio.general/7542
>
> I'm not sure off hand what the latest version of that tool is or if
> there is a proper webpage for it. David, can you elaborate?

No, there isn't one. Here's the latest version:

https://launchpad.net/~diwic/+archive/maverick (for Ubuntu 10.10)
https://launchpad.net/~diwic/+archive/ppa (for Ubuntu 10.04)
https://launchpad.net/~diwic/+archive/ppa/+files/alsamixertest_48.11.tar.gz 
(for other distros)

It currently tests playback only. Before it makes sense to test 
recording as well, we'll have to fix up the input mixer paths in 
PulseAudio. I'm currently working on that, and making good progress.

-- 
David Henningsson, Canonical Ltd.
http://launchpad.net/~diwic