No sound after updating to polypaudio

crimsun at crimsun at
Tue Feb 15 18:15:53 CST 2005

On Tue, Feb 15, 2005 at 02:09:50PM -0800, Justin Mason wrote:
> It'd be great if Hoary could set up the dmix plugin by default,
> btw -- that makes things a lot less painful for those of us
> with low-end sound hardware and on-board chipsets.

Not feasible currently for four (4) reasons:
1) dmix and dsnoop are both less than optimal in terms of mmap and shm
2) quite a bit of sound hardware does not cooperate with dmix
   (orthogonal to the reasons mentioned in [1]);
3) "hw:0" device is often misconfigured by default, and "plughw:0" is
   necessary. On the other hand, "plughw:0" can't be shoved into an
   .asoundrc because one also needs to specify rate and period_time
   for a dmix virtual device for those instances where "plughw:0" is
4) generating a viable .asoundrc (wrt dmix, the simplest case) for the
   widest set of common cards is a misleadingly complex issue. I'm
   currently hacking up a python backend to do exactly such, but
   isolating problematic hardware from [2] and [3] and also accounting
   for latency settings on various motherboards is proving to be quite

Please allow me to reiterate: it's fairly trivial to manually test-and-
set, but automatically generating a dmix target is well, less than

Oh, and I should mention that "plug:dmix" (which is an included-by-
default virtual device) should cover nearly all the problem cases ([2]
and [3]) I mentioned above. Except that again, it often "almost" works,
which brings us back to square one.

Daniel T. Chen          crimsun at
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