My DM is having intermittent ball launch issues not going all the way around to the upper flipper skill shot every time and hitting the left most lane guide area and bouncing down to the pop area. It must be a mechanical issue with the launch ramp and loop guide placements/shape. I have replaced the coil, sleeve,bell armature, driver transistors, and of course the launcher coil bracket is adjusted perfectly and voltage is good. The launch is never weak and the problem seem to be some sort of weird intermittent ball bounce issue. I acquired the machine like this and assumed it only needed the usual coil/sleeve fix and never had a known good state to work with. It all happens so fast I never get to see what is actually causing the issue. Shots to the right loop from the flippers have smooth flow and no issues. Any ideas or past experience on this?