Over the last month or two I have been putting together a MythTV
machine and am most of the way there. The one problem that I can't
solve, and can't find much information on, pertains to the quality of
the audio.

My problem is that the audio I hear when I watch LiveTV or record a
show is horrible. It sounds like it is recorded at a very low
samplerate and comes through only in mono. Testing via the 'aplay
/dev/dsp' method shows an 8000hz mono stream and the sound output is
very similar to what I hear in MythTV. If I force aplay to use a
higher sample rate or stereo then it plays back the audio in very
short bursts at a very fast speed every few seconds, all the while
reporting a series of 'underran!' errors.

If I record using sox then I can grab much better sounding audio in
stereo at higher sampleratesrates (44100 was no problem). Thinking it
could be a duplex issue I opened another terminal and played the audio
stream as it was recording, there didn't seem to be any problems with
playing back the higher quality stream while audio was still being
recorded. I also tried recording a program in MythTV without watching
it (just leaving the main menu screen up) and when I went to play it
back the audio quality was no better to LiveTV.

I've done most of my fiddling using the onboard Nforce3 audio of my
motherboard, which uses the intel8x0 module. I also tested a CMI8330
based PCI card and found the same mono/8000hz problem as with the
other card. In both instances I tried various mixer settings from 10%
up to 100% and have still had no luck. The system is Gentoo based with
a 2.6.9 kernel if that matters. I'm getting video from a BT8x8 card,
tried a couple as I had them around and could think of nothing else.
If anybody wants to see any mixer settings, logfiles or any other form
of output I can provide it, but have to admit I am not sure what
information would be most useful. I am unsure if this is a hardware,
ALSA, MythTV, etc problem.

Thank you in advance for any help.
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