Some buzzing, if detected can be considered a normal part of the panel's life and use.
That said, what you're describing (6 feet away) is not considered normal. I'd definitely recommend calling 800-SAMSUNG and get the unit serviced.
Keep me posted.
I bought a LN46A550 two weeks ago. It begins to buzz after watching tv for 10-15 minutes. The buzzing is high frequency sound from the back of TV, not from spearkers. Is it a common problem?
I noticed it buzzes louder when displaying bright pictures, I can hear this noise 6 feet away from the TV. I tried to adjust backlight, but it doesn't help.
It is a bit difficult for me to bring it back for exchange. I'm wondering if this is a problem that can be fixed by a Samsung technician. Any idea?