Has anyone ever seen this?

When my YAW motor is connect to the 32-bit Alexmos board (with no battery connected; no USB power) the motor has a noticeable amount of resistance when spinning manually. If I disconnect the servo connector the resistance is not there anymore. Again, no power is available to the motors.

I believe the pitch motor is doing this as well. Not sure on the roll...I just didn't want to remove the motor just to check.

The problem I'm trying to solve that when the YAW motor is powered up and turning the slightest bit of resistance (light pressure from my finger) the gimbal start to turn back and forth and stick command don't work.