We have the exact same issue. It affects two Roku based TCL TVs, and two Roku sticks. Rapidly changes volume, changes apps, downloads apps, turns off, turns on, whatever it wants. Pretty sure it created a new user in the Netflix app. No amount of power cycling, resetting to defaults, referring to ANY of the troubleshooting has worked. I’ve even gone so far as to replace the IR sensor control board in one of the TVs. That seemed to resolve the issue for a couple of weeks, but now the problem has returned, and infected the plug in sticks.