In version 4.42, the stitch regulator was found to have this problem.

Check the motor ratio

1. Go to Folder -> Diagnostic -> Motor Settings (password:motor) -> Additional Settings

2. Click on the motor ratio number. If it is not 1.475 or around there then it is the problem and will cause a runaway condition.

3. Select the Motor Ratio button (Nothing will happen after this button is selected)

4. Turn the hand wheel a few times counter clockwise

5. Tap on the “Motor Ratio” number (Not the button) and verify the number is about 1.475. If not repeat steps 3 and 4. 6. The problem should be corrected.  Try you machine and verify it is working correctly.