My Samsung TV does the same thing! It was working fine and then all of a sudden started to turn on and off on it's own. I tried unplugging , didnt work. I unplugged HDMI connection, didnt work. It shouldn't be doing that, especially since I bought it roughly 3 years ago. Not even my old Sony TV of 8 years does that or stopped working for that matter!! I now realize that it's happening to almost all the Samsung smart TV's, with numerous compalints from customers. I'm highly disappointed in Samsung. I even recommended it to several of my friends and family and now theyll have to endure the same issue. Money down the drain.
Been there and done that, had the same issue with my first NU7100. Acccording the to support I was on the latest version. That was before the TV Totally DIED! Replaced it through Best Buy and guess what, this TV had updated firmware. Expect it to die, it will, The second one, the display went, returned that one and then the third one died about 40 days after that. Not to happy with samsung right now. Been through 3 of these now.