Bottom line - I bought a Monster AV700 Audio Video PowerCenter to try and see if it would help the TV - believing firmly that it would not but I could check the box with Mits Service weenies plus I could always return it to BestBuy. Surprise! The TV seems to be all better and the DVR audio dropout disappeared. Even recordings where the audio was dead are now good.
Honestly, I have no idea if the PowerCenter actually did the trick but I didn’t change anything else (and maybe it won't last but I'm keeping my fingers crossed). So – it may be worth a try or tell me I’m nuts – just wanted to pass on my personal experience. Also not making a pitch for the Monster product – it was the cheapest one at BestBuy that claimed to clean up the AC power. Hope this helps.
Edited by Scott2, 16 February 2009 - 12:39 PM.