When Samsung issues a firmware update, decoding may change. THIS IS NOT A BUG. Samsung has been known to drop a decoder since and this is only a guess, it wasn't in the product spec.
Also your video is not 1080p so it may not be full screen. Try the OSD Menu and Tools button to see if any offer is made to play full screen.
In the USA, 1800SAMSUNG for fast answers.
And the chat at samsung.com has answered a few for me.
Hi, i've got an UE65HU8200 samsung tv and recently, it started to play up. I have an external hdd which I play movies on, had it for a while now, and it never made any problems, now, it plays movies half screen, or they are not arranged properly onto the screen, even the movies I have previously played and seen properly are on half screen now, so, something happened. I have tried formatting the hdd but no success. I have uploaded a few pictures so you can make an idea of what I mean. Thank you
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