I've been having this problem for a while. The problem is, when I am in HDR mode, the colors seem to be very washed out, at least for my PS4. I checked the Roku app and in the expert picture settings, I see that the "low power" mode is permanently on when I'm viewing HDR content. I can change the setting outside of HDR but for whatever reason I can't when I'm in. Look, I have looked everywhere for a solution but I can't find anything that works. If you can give your two cents it would be very appreciated.