Is there a thread out there about the audio cutting out on the S3?
I was one of the early adopters and haven't had any problems until now. I'll be watching something live or recorded and the audio spits and sputers for 10-15 seconds and then is back. Rewinding just replays the same audio error. Don't see any pattern with HD vs SD or any particulr channel.
Do you see any degradation of the video signal? There's a widely-discussed syndrome in which the sound drops out entirely for a couple of seconds, followed by a burst of "pixellation" in the video. I don't know if it's been resolved, but at least one user (SCSIRAID, if I remember correctly) has sent a hard drive containing corrupted data to TiVo for diagnosis.
I had a bad digital output on my TiVo, but in my case the audio would drop out at different points if I replayed a show, so I knew the problem wasn't with the recorded material. I paid the after-three-months fee to swap out my TiVo for a new one, and then had my cable company send out an installer to re-authorize my cable cards.
Your problem sounds like something in the datastream. If it turns out that you also see the pixellation in the video signal, welcome to the club. We're waiting for a fix for this. I'm convinced it's not a cable-company problem since people experience it with a large number of cable providers, but others might disagree.