Re: [Openvortex-dev] Low volume, distortion, etc

[J. Gordon Wolfe]

> I did exactly this, several times - there are no differences in playback
> on my system (Aureal SQ2500).
> 
> I'm not experiencing any clicks during playback, but I do experience
> shifts in stereo. It's as if the channels spontaneously reverse
> sometimes. this behaviour is (vaguely) linked to the system's load. For
> example, it happens a lot more in mplayer than in xmms. switching
> between OSS or alsa output has no effect on the problem.
> 
> Does anybody else have this problem?

Oh thank god its not just me!  That problem's been driving me absolutely
crazy!    I have a sq2500 too, btw.  I'm just starting to dig into the driver
code and try and figure out whats going on, but its pretty slow going as I'm
not really a driver developer.  As you said, the problem is sort of related to
system load, though I wouldn't say that it will always swap under load or that
it will only swap under load.  My feeling is its got to have something to do
with buffer underruns, though I haven't figured out a good way to test that
hypothesis yet.  I suspect something is done differently after a underrun
versus when a substream is started, and that makes the difference.  I say this
because when the channels reverse, if I pause and then unpause XMMS the
channels unswap (based on dmesg, I think pause stops the substream and unpause
restarts it.  There are pause and resume substream functions in the code, but
I don't know what if anything uses them).  If anybody with more knowledge
would care to comment on this problem and/or possible solutions, I'd
appreciate it!