Re: [Alsa-user] using dmix causes silent output with snd-cs46xx (1.0.10rc1)

[Takashi I. <ti...@su...>]

At Thu, 19 Jan 2006 13:55:38 -0600,
Joel Bison wrote:
> 
> On 1/19/06, Takashi Iwai <ti...@su...> wrote:
> > At Wed, 18 Jan 2006 22:50:36 -0600, Joel Bison wrote:
> > >
> > > I'm having some interesting trouble getting dmix to work properly with
> > > snd-cs46xx, using the 1.0.10rc1 bundled with 2.6.14.3 kernel.  If I
> > > run two instances of "alsaplayer -o alsa -d plug:dmix file.mp3", they
> > > both appear to run properly (e.g., time and progress meters increase),
> > > but no sound is produced.  Using dmix via asound.conf behaves
> > > similarly.  Alsaplayer plays fine when allowed to have exclusive
> > > access to the sound device (i.e., with no "-d plug:dmix"), but a
> > > second such instance blocks until the first exits.
> > >
> > > A subquestion here is: why is concurrency not working automatically,
> > > without "-d plug:dmix"?  I read that my >= 1.0.9rc2 ALSA defaults to
> > > using dmix for non-hardware-mixing soundcards, which includes my
> > > CS4624-based Cirrus Logic soundcard (as per the soundcard matrix).  Is
> > > that maybe the real problem, with the explicit dmix just confusing
> > > things?
> >
> > cs46xx doesn't require dmix as long as you compile with CS46XX_NEW_DSP
> > option.  It supports h/w mixing.
> 
> Thanks for the reply, Takashi.
> 
> Thing is, I have CS46XX_NEW_DSP turned on, and yet I'm getting the
> second sound access blocking rather than mixing.  Is there something
> special I have to do to enable hardware mixing?

No, it should work as it is.
Could you check whether you really compiled with NEW_DSP config by the
number of substreams listed in /proc/asound/card0/pcm0p/info?

Also, how did you test the multiple playbacks?  As a simple test, try
to run "aplay somefile.wav" on two terminals at the same time.


Takashi