Originally Posted by Vinterbird
If I'm about 12 feet away from the TV, which is where I normally sit on the couch, I should not be able to hear any kind of buzzing even if it was displaying a pure white screen with no audio? If so, then I really do have a faulty TV (or as the dealer has been trying to tell me, that is totally normal for a plasma).
As Randy pointed out, there has been a lot of discussion on this lately. I've kind of been staying out of it since there can be a lot of frustration around the issue, as already seen above. So, before I get accused of having poor hearing or not being able to distinguish ambient noise from the TV, I'll just say that I'm not trying to convince anyone of anything, I'm just offering my experience.
I have all wood floors (sound travels a LOT in my house) and have now had the TV both on a stand a couple feet from the wall and wall-mounted. Under normal operation (just watching TV) with sound muted, I have to put my ear toward the back of the TV to hear an actual "buzz". At my normal listening position (11'ish feet), if I pause on an all-white screen and have sound muted, I think I can hear some faint electronic hum but I can't tell if it's the DVR or TV - either way, I have to concentrate on it. If I have the XBOX360 on, still with sound muted, I can hear it "whirring"/"humming" and it covers the previously mentioned "faint hum". Under normal circumstances (i.e. the sound isn't muted) from my normal listening position, I haven't ever noticed the TV/DVR, even during quiet scenes. If the XBOX is on, I can rarely hear it during quiet scenes.
A lot of people go looking for issues and consequently find them. Whether or not that means they have a faulty TV...I dunno. But I've read several instances (Randy's friend included) of people having an audible buzz, getting a repair (tightening screws, replacing a board, or whatever) and having the issue resolved. If you can hear it with the sound on, from 12 feet away, I'd do something about it - no matter what other people think. For people that sit 12 feet away but can only hear it with bright screnes and the sound muted, it might be worth having checked out, but I'm not sure I'd risk an actual return or exchange in that case.