USB headset ... ?

Alexander Leidinger Alexander at
Thu May 18 08:57:10 UTC 2006

Quoting "Marc G. Fournier" <scrappy at> (from Thu, 18 May 2006  
04:55:11 -0300 (ADT)):

> On Thu, 18 May 2006, Alexander Leidinger wrote:
>> In case you want to play music at the same time you are using a   
>> headset, you can activate the virtual channels for the audio device  
>>  with a sysctl. This way the sound system allows to open /dev/dsp   
>> multiple times and mixes everything together and you don't need to   
>> have more than one soundcard.
> You mean, I can actually hear GAIM beep on new messages while listening
> to music??


> I figured I had to be doing something wrong that it didn't work :(  Do
> you happen to know what the sysctl is for this? :)

Not exacly (can't look it up ATM)... there are two. One is for setting  
it to a specific number of virtual channels, and one is to let the  
sound system automatically add some upto the amount you allow with the  
sysctl. It's in the sound-MIB (hw.sound?).

Do a "sysctl -a | grep pcm". If the output is "hw.sound.pcm0.XXX" run  
"sysctl hw.sound" so see a complete list of sysctl's available. Pick  
one of the "vchan" ones and change it from zero to an arbitrary  
numer... e.g. 4 to be able to let 4 applications play at the same time.

I think we should activate vchans by default... anyone with an idea of  
the number of channels we should provide by default (warning: bikeshed  


--  Alexander @ PGP ID = B0063FE7     netchild @  : PGP ID = 72077137
Nondeterminism means never having to say you are wrong.

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