after watching a 4K movie and returning to the main menu the screen with rapidly and lightly flicker. If will continue doing this on the menu or watching a standard HD movie. It’s almost as if the Roku has trouble switching back from 4K to a lower resolution. I have tried switching cables, changing all settings within the Rroku itself and even changing HDMI ports. I have determined that it is in fact the roku itself and nothing else. Anyone have a guess as to what’s wrong? Only resetting the device will correct the problem only for it to resurface after watching another 4K movie.