legnaz,
Sorry to hear that you're having issues with your LN-S2641. Unfortunately, I don't have any way of really being able to diagnose the problem. The symptoms you describe sound like they are better addressed with a technician or our help desk.
I wish I could help further, but they would be your best bet - and be able to tell you if the unit is still under warranty. If I can help out further, please let me know.
--HDTech
I have had a LN-S2641D for about a year now. Recently the screen has been going black after a couple minutes. It works perfectly fine at first, but then it goes black. Sound still works after it goes black, so I know the TV is not shutting itself off. When is goes black, I turn it off, then back on and it works again....then 2 minutes pass and black it goes again. Anyone know how to fix this?

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