So I've been having an issue with a Pi build and I'm curious if anyone else has experience it or has advice. I'm using a Pi 3b with Retropie and this encoder:
https://www.amazon.com/Reyann-Arcade-Encoder-Joystick-Fighting/dp/B00UUROWWK/When hooked up my controls (Sanwa stick, Happ buttons) are responsive and read input correctly. The problem is that when the controls are idle the system is reading phantom inputs from the device. Using evtest and watching the output I'm getting approximately 1-2 false inputs per minute. Some of the inputs are by themselves and some are multiple buttons being activated at once. This is causing an issue as periodically the buttons mapped to Start and Select are activated together, causing games to exit erroneously, as well as all the other problems you'd expect from a game getting input you didn't give it.
Does anyone happen to have experience with something like this? The research I've done makes me think that there may be an issue with the power from the Pi USB ports not being consistent, which causes the encoder to think a button is being pressed. I'm inclined to try a powered USB hub but wanted to see if anyone else had advice before making that purchase.