So I've got a Sabertooth 2x5 motor driver. I uses standard servo connections, and a micro controller can use standard servo arguments to make the motors go in forward or reverse (much like a continous rotation servo). In any case, it connects to a board in the bottom of my robot, gets grounded to the common ground, and through traces the signal lines go to a JST connector to the next stage of the robot (which is designed to be modular for easy teardown). The problem I have is that sometimes the motors move slightly; this usually happens if the motors are not receving any signals if the robot is in idle. Further if I remove the connector and touch the data line pins with my hand the motors will move.
I was wondering if an optocoupler/isolator for the data lines before the JST connector would fix this issue? If not, what would be the suggested way of dealing with this?