I have 4 t100 motors the left motor has recently stopped chattering like the other 3 and spins slowly constantly when the joystick is in neutral position. It has also recently become weaker, only in reverse, than its right side counterpart, even though the code is the same. We have checked all connections, re-downloaded the code and swapped out the arduino, the issue remains. Any thoughts on if the issue is in the esc (fairly new) or in the motor itself, or something else??? Thanks!!!