spntop,
Try reading this thread:
http://forums.cnet.com/5208-13973_102-0.html?messageID=2966490&tag=forums06;search-results#2966490
One of our forum posters ran across this issue, and a fix.
Keep me posted.
--HDTech
I have the tv connected by coax cable directly to wall jack. I am getting a "resonance/reverberation" type of sound or hum with speech when listening to internal speakers only. No problems with external receiver/speakers only. This problem occurs with most, but not all, programs and does not resolve with changes to audio settings. The problem also seems to be independent of channel. It's as if a certain tone of voice induces the problem. I read on another forum about "robotic" sounding audio problems that required resetting tv but this also didn't help. Any suggestions would be sincerely appreciated.

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