Firmware: 1.2.10 and earlier. Settings: HDMI Mode: 3840x2160p 60 Hz Deep Color mode: Auto or 12bit or 10bit Color Space mode: Auto or YCbCr 444 or YCrCb 420 Auto23.976/24 enabled With this settings I get after every 40 seconds a black screen for 1 -2 seconds. somtimes earlier or later. You see on TV that the box has changed to 2160p and 23.976 What works: - Disable Auto23.976/24 -> the movie will run with 60Hz. The are some micro shutters - Set HDMI Mode to 1080P 60Hz -> bad for 4k content - Set Deep Color mode to off -> bad for HDR content - Switch color Space mode to RGB 444 -> in black parts of a movie I get white pixel errors like snow At the moment the best option: Switch to YCbCr 422 -> Seems to work fine, but I think that the colors are not so strong. will test it. Is YCbCr 444 and 23.976Hz a hardware limitation or problem? Can you fix it?