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

[Peter Hercek]

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?