adt0330,
I would suggest, since it's in warranty, that you get a service technician to take a look. I'm not sure what is buzzing or why that issue is happening.
Regardless, if it's coming out of the speakers of the television and those speakers are muted, it seems to be a covered problem and more than likely may be a relatively easy fix.
Why not give 800-SAMSUNG a call to have a service tech take a look?
--HDTech
We have had this TV since Sept. 08 and in the last month or so we have this buzzing noise that comes and goes, no matter what the volume is on or channel. We have the TV sound setting set to OFF since we have a Samsung 2:1 surround sound system where we get the sound from. I have turned the TV sound off and on, still have the buzz. I can def hear it coming from the TV and NOT the surround sound unit. Any ideas to fix this?

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