[linux-audio-user] Mixer problem

[Alex Marandon]

Hi,

I have a problem with my mixer that is I can't record line input without
simultaneous playback. That's very annoying in my situation because I'm applying
effects to the line output of my soundcard with some external signal proccessing
hardware.  If there is playback when I'm recording the proccessed signal by line
input, there is an infinite loop, and that's bad.

When I try to set up my soundcard (SB Live!) with alsamixer, nothing happen when
I press space bar in order to assign capture to a channel, the red capture label
doesn't appear. So know there is something wrong with my setup because I've
already used alsamixer before and it was able to set the capture option.

If I try a graphical mixer like gnome-alsamixer or kmix and check the recording
checkbox for the line input, recording doesn't work.  I have to check the
recording checkbox for the "capture" channel but then, the recorded sound is
played back at the same time, even if line input is muted.

However I have no problem to record sound played by the soundcard synth using
SoundFonts, I just check the recording checkbox and it works. I don't need to
deal with the capture channel.

Any hint ?

-- 
Alex