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

[Peter Hercek]

On 12/22/2010 07:58 PM, Peter Hercek wrote:
> On 12/22/2010 05:45 PM, Colin Guthrie wrote:
>> 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
>> playback).
> Yes, when I did this it was represented as "Line In" in the "Input 
> Devices" tab of pavucontrol. Works well. Well, except this quirk:
>
> I could use this but the problem is that when I do not have 
> pavucontrol or pavumeter (or some other application generating sounds 
> (e.g. like mplayer)) running then the module-loopback drops (the sound 
> from "Line In" stops). The sound resumes when I start pavucontrol or 
> some sound generating application (well I'm not sure whether all of 
> them work but mplayer restores the "Line In" sound). It is interesting 
> that pavumeter cannot restore the "Line In" sound; it reports 
> "Connection failed: Connection refused" instead.
> This error state (when "Line In" is not monitored by the 
> module-loopback) seems to be there also after a reboot. Pulseaudio 
> daemon does not report any errors to messages log when it stops to 
> loop Line In to Output (log level was set to warning). Well, 
> pulseaudio reports "XX events suppressed" ocasionaly, but this never 
> seemed to matter (the sound was not choppy and did not seem 
> distorted). Typically, I have log level set to error to supress the 
> warning.
>
> Any idea what is wrong?

I looked at this better today and found out that the reason the loopback 
sound stops is that the pulseaudio servers exits. It thinks it is idle. 
It looks like when some sounds go over loopback (or pavumeter) it is not 
considered a usefull work (the message was: "core.c: We are idle, 
quitting..."). But when some sounds go from some other apllication (like 
e.g. xmms) or when pavucontrol is running then it is considered a 
usefull work and the server does not get idle. This looks like a bug to 
me. Streaming sounds over loopback is definitely usefull work for me.
Should this be reported as a bug?
Is there some workaround, some way to make pulseaudio server not to 
detect idling?

Peter.