Hi there I've recently put a second extruder onto my mendelmax 2. I got advice for all of the settings to change on the marlin firmware and is working fine except the seond extrude E1 motor is not turning properly instead it jitters. I've changed the motors over E0 and E1 and still the same problem. Then I got some advice to up the current from 135 to 145 using this gcode M908 P4 S145 (0-255). When I did this it started working so I looked for the code in the firmware and changed it and uploaded and now its back to jittering again. Not sure what to do next as when I retired sending the gcode it doesn't seem to make it work... Any help is greatly received...Thanks