My moat opto was acting the same way, another pinsider said to adjust the bolts on the coil stop but this didn’t affect my ball height/opto level so I put it back, now it has worked perfectly. Maybe it was a loose connection? On a side note how do you adjust the flipper strength and can coil strength be adjusted for the catapult mine will only launch the ball all the way around about 30% of the time, about 45% it dribbles of the end and the rest it rolls back down re registering another shot.
Other than these small issues I love the game! I just need to buy some invisiglass or similar.