Apple TV 4K White Flashes

I'm seeing occasional white flashes on the screen. Easily seen on the screen savers but I've seen them on content too like Netflix and HBO.

I saw them about every 10 to15 minutes the flash looks like a single frame of digital noise.

My setup is ATV4K to Denon X2400H to a Vizio M65C1 class. I have brand new Monoprice high speed certified premium HDMI cables. I've turned all video processing from the Denon.

I saw flashes every 10 to 15 minutes when the setting was 4KSDR 50Hz.

I did a video settings reset through the Apple TV and it changed to 4KSDR 60hz. I have seen an occasional flash but very infrequent maybe one every couple of hours. . So there’s an improvement but still something is going on.

Software issue? Hardware issue?