So some new information on my end. I went away for the weekend and left the TV Unplugged for 2 days. When I came back, 2160RGB worked for like 10 minutes straight. Then the on and off flickering started again. Over time it seemed to get worse, like at first every 10 seconds. Now its mostly no signal again with the occasional showing the picture flicker. The only reason I got this TV was because of the wide color gamut, if I can't use it I should return it but I don't want the hassle if this can be fixed. I don't know what else to try though and don't understand why leaving the TV unplugged for a couple of days would let it work correctly for a few minutes.Can't imagine the mount would have anything to do with it, unless the connection is loose? Also, maybe one bad cable, perhaps two, could cause the issue, but if you've tried numerous cables with the same issue, that should rule out the cable. What you are describing sounds like a cable bandwidth problem, but I've had no problems with the Monoprice certified HDMI cable.
If you have the most recent Vizio firmware, PS4 firmware (4.50 I think?), using a 6 foot certified cable with a direct connection, and nothing else connected to your PS4 Pro ala PSVR, I'm stumped.
Good luck, I hope you solve this issue!
Hdcp 1.4 doesn't make a difference, over 10 cables including multiple monoprice certified premium HDR cables doesn't work, ports 1-4 no difference. Limited, full, automatic, 2160p RGB, nothing gets a steady picture with subsampling on and 2160p RGB except I can get 10 minutes of picture by unplugging the TV for 2 days.
Its frustrating and time wasting. I have to use YUV420 to get a picture with subsampling on and that's not 10 bit color, RGB is. Is there anyway to force a firmware flash if I am already on 3.014?