While I didn't find this model on samsung.com did you try the usual unplug all the cables, remove the power cord for about 10 minute tech trick?
Bob
Hello we have an issue with our TV Samsung UE40S800. For some days it doesn't work at all. For PS3 or PS4 it shows nothing. Also for digital TV we have to reduce image quality in order to see itl
Do you know if it is possible to solve this problem or we should sack our TV? Thanks.

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