Hold up. HDMI and USB are very different things. Never confuse the two or think of them as "same thing." You can get led down the wrong path with support. Briefly, HDMI is the video output, and USB on your Roku is for power (USB has many other functions on many other devices, but I'm simply talking Roku Stick for now). You indicated both, but then indicated power from the wall. I suspect changing that sentence to "Unplugged/plugged from HDMI port" would be accurate, and will proceed that way.
You said "same problem" but I'd like to be absolutely sure what your Roku symptoms are, as a similar but not same problem could have a very different solution.
Describe the problem. Walk through what happens, without using words like "same." You've described the troubleshooting steps, but a description of the problem is missing.
We can probably figure this out, just let's make sure we're solving the correct issue.
DBDukes Roku Community Streaming Expert
Help others find this answer and click "Accept as Solution." Note: I am not a Roku employee.