Updating my post (2 years later). It turns out my TV was buzzing because it was on the same circuit as a dimmable light socket in the house. That dimming socket had a non-dimmable CFL bulb in it. After replacing that bulb with a standard bulb, no more buzzing.
wow! are you serious? makes me wonder if any of the other buzzing issues are due to this. I got a Belkin current conditioner as soon as i got my plasma, its managed to keep away any power issues (and it looks great) In case anyone is wondering it makes a big difference, I had it hooked up to a toshiba LCD and there was noticeable noise without it
If you have ever put a non dimming CFL into a dimming curcuit/socket you can see how "noisey" it is.
I noticed it was the problem when I got up to turn off the light completely, as soon as I did the buzzing stopped. Put in a regular bulb... no more buzz. 100% sure of it.