Unplug the set for a long time with all HDMI cables, connections and main power unplugged.
If it's the old HDMI chip issue then it will clear up. If not, time for one other last thing. See if the firmware has an update on the Samsung web site for this model.
After that, get repair estimates.
I have a Samsung model un46eh5000f TV which has worked perfectly for a couple years. I've also had an Apple TV 2 connect to it for a while with no issues.
Just upgraded to Apple TV 4 and my display began going black for a few seconds, about every 2 minutes. I've tried a factory reset of my TV, updated apple TV software, tried a different HDMI port with no luck... what's strange is that it continues to go black periodically even when I disconnect my Apple TV entirely.
Has anyone experienced this?