I have just purchased the 58PUS7855 and connected it to SKYQ box. It all came up as normal but when I tried to view uhd content sky said I need to enable uhd by pressing red. After i did this I created a weird fault where the sky picture/sound flashed on and off. I have made sure the source settings are on uhd and everything seems set up right. When it happened I factory reset to be able to watch regular HD sky and that worked. I was going to return the TV today but had one last go. It worked and managed to watch a uhd film on sky. I went on Disney+ via sky app watched a film then went back to sky and it started with the fault again. I have recorded it just to see if anyone knows what it could be. I have tried 2 different hdmi cables.