I think you are going to have problems unless you switch over to pp hydraulic drives, or go back to the pro monitor running the drives.    actually the problem isn't the motors so much as it is the the CIH pwm valves.  that system is designed to run at a higher hertz than most systems.  go to the section that shows how many hertz you are driving your valves at, and pick the highesthertz level you can (hopefully above 200), see if that helps.