Quoted from Danno66:
Howdy Folks! This is my second week of owning a new Ghostbusters Le. I have most of the games problems fixed, airballs and one other are still present. I won't address airballs here because I am buying a protector, the main problem with my machine is that most of the time I get the ball stuck in an endless loop in the pop bumper area around "Gozer the Gozerian". This problem spells out worn playfield and pop bumper rebuild in <2 weeks. Essentially the ball will go between the slingshot, the second pop bumper, the target, and back again for up to 45 MINUTES!! Yes that says minutes. For a plus it gives me time to go to the bathroom and answer emails for a minus it ruins the fun really fast. I wasn't sure of the upload limitations so I filmed a 15 second version and put it on youtube. I should add that I set coil power on Soft and slingshot down to 18 also leveled the machine many times without success. It's running 1.5 software. Any ideas would be appreciated, for now I have disconnected one of the pop bumpers but really I don't like that solution a whole lot... Here's a link: » YouTube video
The only short answers I can think of are to remove the 3 screws holding the city.
Change the rubber on top, going both a hair "looser" or "tighter", and and some wax in the area.
With the city off, see if either of these 2 minor adjustments make a difference, then move to changing the gap in the Pops. There are also 2 single posts with rubbers there, also try tighter and looser rubbers up there.
A subtle change, can result in a bounce change.
When I changed mine to GITD, bounces in the Pops changed, as all the replacements, were "tighter" than\black stock.