Watching TV via my Tivo (Comcast cable) at 720p or 1080i worked perfectly, but at 1080p, (roku, youtube, blu-ray, etc), I would get flashes of static on the screen every several seconds - pretty annoying

I recently bought a 4k Roku, and when I set it to output at 4K, the static issue was much worse - flashes of static on screen constantly.

I recently bought a 4k Roku, and when I set it to output at 4K, the static issue was much worse - flashes of static on screen constantly.