@RokuDanny-R I wanted to post some photos of what the green screen looks like on my TV.
Here it is with the input set to receive Dolby Vision:
And here it is with the input without Dolby Vision (looks normal)
Please forward this to the support team and feel free to reach out if anyone has questions.
I have the same issues using the Roku Ultra and X900H. Can confirm that if I change the HDMI signal on the TV to "Enhanced" but non-Dolby Vision and disable the Dolby Vision output on the Roku, I never see a flicker. But if I enable it on the TV and actually output in the Dolby Vision format, I see a flicker every 10-20 minutes. Doesn't matter which app is being used - it flickers even on the home screen.