I'm trying to enable HDR on Windows 10 on my LG C1 OLED TV, but getting some weird random green flickering pixels. Both my PC and PS4 connects to a 8K HDMI switcher, which in turns connects to the TV via a 50 ft 8k HDMI cable. I suspected the 50 ft cable might be the culprit, but the PS4 has no problems with HDR with this setup. This may be because it's the PS4 slim, which is only 1080p.
This is what the green flickering pixel looks like (not sure how to post mp4s here): https://i.imgur.com/dQWpjAb.mp4
What's also bizarre is that if I leave Windows 10 "Stream HDR video" on, then the preview video of the skateboarder gets really crazy (as shown below). Even if Windows 10 HDR turned off completely, it seems HDR movies still seem to work (since the TV doesn't show washed out colors like my main non-HDR monitor), but the green flickering is still present.