This used to happen on my POTC all of the time--but only when the ball was automatically launched. It didn't have enough power to go all of the way up the ramp and would settle at the same spot as yours. I determined that the plunger tip was slightly scraping the ball launcher during automatic launch. I took the plunger off, used two pliers to stretch the spring about 1/4" longer. This moved the plunger tip back 1/4" and no longer touches the ball launcher. The ball almost never gets stuck on the ramp anymore, and doesn't affect manual ball launch or appearance.