Sound driver weirdness

Warner Losh imp at
Fri Nov 4 11:29:56 PST 2005

> > % fstat | grep dps
> "dsp"

Same results.

> > Why are my vchans disabled, what does that mean and what can I do
> > about it?
> That means at most, only single process (sound apps) can acquire the
> sound device (vchans = virtual channels).
> 1) Try enabling vchans by increasing the value of both
>    hw.snd.maxautovchans and hw.snd.pcm0.vchans (4 is a good start).
>    After that, you probably need to reduce the value of
>    hw.snd.pcm0.vchanrate to 44100 (only if necessary).

same results.

> 2) Try to use other 'simpler' apps, such as mpg321

cat > /dev/dsp gives the same results:

cat > /dev/dsp
/dev/dsp: Operation not supported by device.

> 3) hm.. I don't think my recent commit against both dsp.c/mixer.c
>    cause this problem (maybe?). Note that there was also a commit by
>    DES, so you probably need to back off dsp.c down to rev. 1.85

I'll have to give that a spin...


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