They will usually have you factory reset and update firmware then if it's bad still, arrange for repair.
Hello I have a un66ku6290F. The picture started cutting out any time you change the channel or when the scene goes black. It will kick back on once the scene is brighter. I just got done replacing the main board and the power supply board without any luck addressing the issue. I am thinking it might be a back light issue? I don't understand why a bad backlight would cause these issues. Is the backlight worth replacing?

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