datasam,
The buzzing sound is probably indicative of a serious malfunction. I would definitely recommend calling 800-SAMSUNG to have your unit serviced.
--HDTech
Hello Samsung,
Model:40A650A1F ModelCode:40A650A1FXZA
I've had my TV for less than 3 mos and have several problems: 1) Normal sound sporadically replaced by loud rough buzzing (fixable with a manual "reboot"); 2) Randomly shuts off (sometimes "reboots" on own); 3) The remote does not function even w new batteries; appears to not communicate at all with TV (no blinking TV light, no response). Older digital Comcast-controller can no longer turn it off either-although it can change channels. To turn unit off, I must unplug daily. Picture is fine; great actually. Would appreciate your help. Thanks...

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