Madavik,
I'm sorry to hear that you're having this issue.
It's difficult to diagnose the issue, however that could be repaired under warranty. I'd recommend calling 800-SAMSUNG or filling out the Online Service Request Form here:
http://www.samsung.com/us/support/service/request
--HDTech
Hi,
I have a Samsung LN40c670, and it's only about 2 weeks old. Sometimes it will turn off by itself. It only does it within the first 5 minutes that it is on. When it does so, I can't turn it back on. Sometimes it will turn itself back on right away, or within a few minutes. When it turns off, the red light at the bottom right corner of the tv stays off too. Like I said, it only does this within the first 5 minutes after I turn on the tv. Once it turns back on, it never turns off again and it will stay on for hours, or until I turn it off.
Any ideas? I can still return it to the store for a replacement, but I was wondering if there is anything I can do. I also checked to make sure none of the timers were on.
Any help is appreciated!

Chowhound
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