Hello. First some history on this problem. When I got this machine a few months ago SHOOT multiball was always three balls. I realized after reading the manual that it was supposed to be two balls. I traced the problem to a trough ball three switch error. After adjusting and aligning the two opto boards the error went away and SHOOT multiball became a two ball multiball as expected. Fast forward to yesterday. I replaced all four balls with new balls and the first time I get a SHOOT multiball it was a three ball multiball. Subsequent SHOOT multiballs are also three balls. My first thought was that the trough error had returned but it hasn't. Any ideas what else could be causing this issue?