I have a Sabre 1500 with an A2100 control. BDS4 Servo Drives. I can move the Y and Z axes just fine. The X axis however jerks, I'm guessing a servo oscillation. The control then errors out with a Foldback error. I can move it very slowly for a bit with the MPG but any speed at all and it begins jerking. Anyone have any ideas - Drive? Motor? Feedback? Thanks