[pulseaudio-discuss] Sound output is muted at 16% volume

Colin Guthrie gmane at colin.guthr.ie
Mon Apr 12 06:02:08 PDT 2010

'Twas brillig, and Marti Raudsepp at 12/04/10 12:03 did gyre and gimble:
>>>> 'Twas brillig, and Marti Raudsepp at 11/04/10 21:06 did gyre and gimble:
>>>>> I tried working around this by changing the PCM level in alsamixer,
>>>>> but whenever a new client connects, PulseAudio thinks it's smarter
>>>>> than me and resets the PCM mixer -- to somewhere between 0.00 ...
>>>>> -0.60 dB (?!), and sets the master level to 0% again
>>>>> So there are 2 distinct problems:
>>>>> [...]
>>>>> 2. If PulseAudio wants to maximize some volume controls, it should set
>>>>> them at 0.0 dB, not -0.60 dB
> On Mon, Apr 12, 2010 at 1:56 PM, Colin Guthrie <gmane at colin.guthr.ie> wrote:
>> This is a product of how PA controls the volumes. It maintains
>> completely control over the whole pipeline in order to adjust the volume
>> in the most appropriate way.
> Yeah I know that! The bug I'm describing above is that it should set
> the volume to 0.0 dB, not randomly one of -0.20 dB or -0.40 dB or
> -0.60 dB like it does now.

Well it depends. If the first mixer in the pipline manages increments of
1dB and the 2nd mixer offers increments of 0.2dB then to obtain a given
volume then for some volumes, both mixers will be set in some capacity
(AFAIK - I've not really studied this code too much tho').

e.g. say pulse wants a dB of 48.4dB. The alsa master slider says that
when it's set to 0 it offers 48dB, so PA sets it to 0 and uses the PCM
control to get the remaining 0.4dB.

So I guess there is scope for this to happen. I suspect that whatever
the problem here, that with updated info from the alsa driver side, the
problems will ultimately go away.



Colin Guthrie

Day Job:
  Tribalogic Limited [http://www.tribalogic.net/]
Open Source:
  Mandriva Linux Contributor [http://www.mandriva.com/]
  PulseAudio Hacker [http://www.pulseaudio.org/]
  Trac Hacker [http://trac.edgewall.org/]

More information about the pulseaudio-discuss mailing list