If it was a hardware issue it wouldn’t work with a power source plugged in. And it wouldn’t only be on a certain state of the software, for example it’s only the Lock Screen that’s affected, but after that nothing else? Doesn’t make sense. It’s the software
This makes sense. I wonder if it's a sleep/wake state issue. With the magnet sensitivity built into these bodies, it could just be getting confused about when to fully wake up and start recognizing normal touches.