If the game thinks you’ve drained (DMD/sounds go into the end of ball stuff before the ball has actually drained) then reseat the connectors on the trough opto boards. If the game doesn’t think you’ve drained, reseat the connectors on the applicable node board.
EDIT - reading is hard! For whatever reason I thought this was Stranger Things (I think because the 1st sentence said “strange thing” LOL), if this isn’t even a newer Stern just ignore