Whenever the Proton returns to the home position, the front leg retracts until a “home” switch is pressed. In some cases, the switch does not get pressed and the Proton keeps trying to retract the front leg. When the front leg stepper motor is trying to move, but cannot, it emits an unfortunate whine. Nothing is damaged, but it’s certainly annoying. We will soon be posting a video to guide you on how to fix the issue.