You call it in, make it a warranty issue and if they fail, go for refund.
I have a UN43M5300 in my bedroom. I was setting the sleep timer every night and noticed sometimes the TV was still on hours later. Sometimes it turns off, others not.
Then, I noticed an "Off Timer" function that would turn the set off at the same time every night. Nice feature, but It also is erratic about turning the set off. The software is up to date. Anything?

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