A first step might be to determine whether it's an electrical or mechanical issue. If you listen carefully (or use a bulb tester) you should be able to count the number of pulses or steps the Player Unit is getting at the start of a new game. If you get the same number of pulses when it's up as when it does when it's folded down that would imply that the circuit is consistent and that the Player Unit is mechanically taking an extra step in the upright position.

/Mark