I’m having a bit of an issue in calibrating my motors, namely the adjusting voltage to 0.425V part. Two of my motors work just fine and can be calibrated to 0.425V but the other two (X-motor and E-motor) seem to skip around that range. They started off in the 0.05V area and turning them to the left (obviously) eventually changes the voltage to 0V but turning the screw to the right makes it skip from 0.05V all the way to the 3-5V range. The 0.1V to 3V range seems to be skipped entirely. What can I do to fix/troubleshoot this? Could it be faulty soldering and if so which pins on the motor connector should I check to ensure they are connected?