Got this TV the other day, and we were all totally wowed by the picture and sound quality, as well as all the 'internet stuff' it offered - truely excellent. However, once we had turned the volume down a little in the evening, there was a distinct buzzing sound in the room - the whole family noticed.
And it is ALWAYS there when the screen is on, not a huge issue when watching a loud film, but when a silent bit comes along - buzz buzz buzz. There is a whole thread on AVForums about the buzzing - seems you might be lucky and get a unit without this feature, but people seem to think it is capacitors or something.
Anyway, I returned the set and replaced it with another of the same model (thought I might get lucky!)- but that was exactly the same - buzzzzzzzz!
I have now returned that one as well and will try something completely different.