I had a service tech out to replace the panel and asked him about it. He said it could be the processor. I've noticed it happens when I'm watching HD cable channels or blu-ray. If it continues I'd recommend having it serviced under warranty. Call Samsung and they'll set you up with a service tech company in your area. Meanwhile, turning the tv on and off seems to help most of the time, but it shouldn't be doing this. Good luck.
Anyone having issues with the menus being incredibly slow? I have macros on my remote to turn things on\off and when my menus slow down to a snails pace the macros don't work correctly. Navigating them manually is terrible as well as it takes literally 5 seconds for the next option to come up after hitting a directional arrow. I've updated the FW several times to the latest version hoping each time it would resolve this problem but no such luck. I have to unplug the TV regularly to get it working as it should. I can program delays in my macros but there has to be a fix as this is very very annoying.

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