I have seen the same problem. The Roku Pushes 4:4:4 causing problems. There is no way to adjust the settings in the Roku. Everything is done via EDID. Can't wait for the AppleTV 4k....ugh....I also have been doing tons of Roku's due to their better UI, more apps, Amazon, our cable provider is only on Roku, and IP Control. I just wish I could change some settings. I have also had issues when putting the Roku into a matrix. It sees surround sound somewhere, then it goes into surround sound and none of your TV's work. Then you have to reset the Roku. I did find a way where you can force PCM through HDMI. It fixes the problem, but then any surround sound zones don't get Digital surround sound. I have literally install hundreds of the Roku4's and never had these problems. I keep having issues with the Roku Premier, Roku Ultimate, etc. Plus IR control is garbage on the new Roku's. Why is it so hard for someone to keep making a good piece of equipment. I actually just bought 6 of the Roku4's on clerance from New Egg. Just wish they had HDR....What a pain.