So I have a weird sticky flipper issue on my Centaur. I believe it's mechanical in nature, because I can turn off the machine and the flipper stays stuck in the extended position. However I can't recreate by moving the flipper or the solenoid with my finger, it only sticks if fired with the flipper button. It's a wierd one - anyone know what could cause this? *** I did a full rebuild on the flippers maybe a month ago, they worked great for a while before the flipper began to stick.