With the question out of the way, call Samsung for a fix now. If they can't fix it, ask to exchange it for a good one.
I just bought this tv and on all sources the tv will brighten all of a sudden and a while later will dim. or vice versa. I read a lot on the internet and went thru and turned all eco settings to off along with pretty much everything else with the word auto. called samsung customer service and they had me verify that all that stuff was off. they had me do a factory reset and also unplug i for three hours. It still does it. I am set up with an at home service appointment for next week with a company called ASC. Anyone have this issue? Was it able to be resolved? It also loses wifi all the time. Ive read about that too and ordered a wifi range extender. I did a fair amount of research before buying this tv and thought I was making a good choice but I have to say, not too happy so far. Thanks fo any info!

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