If you look at the playfield of the Full House (a 1966 Williams) picture I attached, you will see the two nines are both lit, which lights the red pop bumper, getting 100 points which is correct. However, once you have one or both of the nines lit, when you move your score on the ten digit score wheel by any means, it seems to reset the nines, turning the light(s) off. If both nines were lit and this happens, it also resets the red pop bumper, turning off the light and it goes back to scoring only 10 points. You also lose your full house if you happened to have one. There are two ways to move the ten digit score wheel, by hitting any of the 10 point bumpers and and/or targets, or by hitting the single digit button when it is at nine and it rolls over to the next ten digit. Both ways causes the issue and it does it every time one or both of the nines are lit. Any ideas on the most likely cause?