My Strato-Flite is doing a weird thing that has me more than confused. Not that it is super important but if I drop a quarter in the slot it will knock the knocker and advance the credit. If I drop another one in it just drops right through to coin box with no credit. I see the 25 cent relay firing but no credit. The really weird part is if I manually engage the relay it will add credit. It will not accept another coin until end of game. Anyone have any ideas???