Hello, former employee here. I have the newest 4K box and 65" Samsung QLED tv. This happens almost every day when I come home from work. I turn the tv on, I can hear the sound, but no picture. It works when I unplug it and plug it again or system refresh
by usung the my account app. The thing is I don't want to refresh the system everyday or unplug and plug it back. Before I do anything I also tried unplugging the HDMI cable and plug it back in see if it's the cable issue but no luck. Cable box power setting is set to not to go to sleep.
I imagine you new TV has several HDMI ports. Have you tried each one?
The TV ARC or CEC might be an issue.