Thanks for the follow up @Havok
Please provide us with the following information for further investigation:
-Roku device model, Serial number, Device ID, Software OS/version (these can all be found in Settings > System > About)
-What version/build is the channel affected (this can be found by selecting the channel on the Home screen and pressing the * button)
-Tracker ID when this issue occurs (when you see this issue occur, press the Home button 5 times, followed by the Back button 5 times and provide us with this ID)
- Screenshot of the page your seeing.
Once we have the information needed, we'll be able to forward it to the appropriate Roku team to investigate further.
Regards,
Karla
This issue started for me with Roku OS 11.5 and is finally fixed.
I recently upgraded my Plex Server from Windows to Ubuntu and updated my Roku Ultra 2020 to Roku OS 12.
I don't know which of the above fixed the severe contrast issue but it's now gone.