[pulseaudio-discuss] cannot control input devices from pavucontrol + crashes in recording tab

Colin Guthrie gmane at colin.guthr.ie
Wed Dec 22 08:45:40 PST 2010

'Twas brillig, and Peter Hercek at 22/12/10 16:19 did gyre and gimble:
> On 12/22/2010 01:20 PM, Maarten Bosmans wrote:
>> Why are you using arecord? That way you bypass PulseAudio completely
>> and record directly from the alsa sound source. Using parec instead
>> gives you all the pulse goodies you can handle!
> On my machine, the default is pulse, so it should not matter.
>> If you're saying (I'm not quite sure I understand correctly) that
>> changing mute/volume of the pulse source does not result in a volume
>> change of the audio output of arecord, then that's completely
>> expected. (Well, it could have some effect, if pulse decides to adjust
>> hardware volume, but anyway, it won't be exactly how you want it)
> Well you made me think that what I want may not be possible. If so It
> decreases pulseaudio value to me so much that I'll probably get rid of
> it. Anyway I try to explain better what I would like to do:
> * I have a TV card which does not have any digital sound. The only way
> to get sound from it is to connect the TV card AudioOut to Line In  of
> my sound card.
> * Then I have a bunch of normal aplications which generate audio output
> (e.g. xmms).
> * Now I would like to be able to control these things from pavucontrol:
>     + mute Line In (TV) and control its volume levels
>     + mute and control volume levels of all the applications
> individually (e.g. xmms, mplayer, ...)

Ultimately, hardware loopback is not that common these days. You're
kinda lucky that it works for you.

What most users end up doing is using module-loopback. It's records and
then plays the input. This obviously shows up in pavucontrol as a
regular stream and has fully (and independent) volume control and muting
due to the fact that PA support per-stream volume control (at least on

Perhaps forgoing your hardware loopback and using module-loopback will
be the easiest route for you too?

Simply call:
pacmd load-module module-loopback

Then just use pavucontrol (you'll likley have to adjust the filter at
the bottom right) to move the loopback streams (one for recording, one
for playback) to the right devices.



Colin Guthrie

Day Job:
  Tribalogic Limited [http://www.tribalogic.net/]
Open Source:
  Mageia Contributor [http://www.mageia.org/]
  PulseAudio Hacker [http://www.pulseaudio.org/]
  Trac Hacker [http://trac.edgewall.org/]

More information about the pulseaudio-discuss mailing list