I was using FireTV Cube and recently switched to latest Shield. Both of them were playing content fine till I went playing with receiver settings and discovered

I was using FireTV Cube and recently switched to latest Shield. Both of them were playing content fine till I went playing with receiver settings and discovered that I didn't have HDR enabled on this HDMI port. After enabling I started to have a lot of jitter and blank outs (though while it worked - picture was better then before). Solution was to buy "premium" HDMI cables that are rated for 4K HDR