[mythtv] A/V Sync Issue

[MATTHEW WILLEY]

Hello...  I posted this originally on the users list, but I have much more info now so I thought it might be appropriate here.

I cannot get HDTV to playback in sync.  SD is fine, but HD will not work.  It is looking like this is related to the AV-710 sound card I have.  Here are the symptoms:

If I set alsa to a rate of 44100 video looks just about right, but the audio is slow and the whole thing continually falls behind live programming.

If I set alsa to a rate of 48000 audio is perfect, but the video constantly holds.  The verbose log shows A/V diverged by 3.XX frames...  This is a consistent issue once it starts streaming.  

I am using AC3 passthrough with the standard decoder.  This is the case with both 18.1 and the newest SVN yesterday.  My CPU never goes over about 60%.  It is definetly appearing that it is an issue with playback involving audio.  BTW, multi-track rate locking does not seem to make a difference either way.  Does anyone have any thoughts on what to try?

TIA,

Matt