It's just a generic HDCP error, but I don't want to hijack this thread with an unrelated problem. I have had the red tint issue for quite a while now, even on my previous TV. I have 3 other non-Ultra Roku in the house and they play the same videos fine. It's a problem only with the Ultra.
But FYI,The HDCP problem started a few months ago when I got a new TV. It's a Samsung model QN85QN90BAFXZA. The Roku Ultra seems to have issues when I come back to it from another input. The screen will flicker a little bit and it seems like it glitches out, then displays the main menu in less than 4k. If I try to watch Netflix or Disney and probably others when the screen is in this state, I get the error and have to restart the Roku. I'll make a new post if you are interested in looking further.