I just had a thought. There are 4 allen screws on each side of the gantry that connect it to the motors. If you loosen them up but don't take them out, with the machine off, and then turn the machine on, it will automatically adjust the the gantry. Once it stops moving back and forth and the machine is idle, you can tighten them back up. It's worth a shot. I am thinking it could be out of wack and maybe putting strain on the motor.