I have a couple games where the balls fly off one of the ramp returns: a Fish Tales and a Black Rose. They're both level, I've tried messing with the pitch to see if that helps, but I just can't seem to fix it. I'm not sure what I can modify about the ramps themselves to change this.

What factors cause a ball to fly off a ramp return? Knowing what could be causing it might help give me an idea what I could do to fix it.

Thanks, I'll check the instruction manuals and see if there's information on what the correct amount of washers should be, and check if mine match it.

They're within the normal pitch on the pitch gauge, and I've tried raising and lowering to see if I get any noticeably different of behavior, but I don't, so I'd expect it's something that's gone wrong with the ramps themselves.

Great idea, I hadn't considered that, I'll make sure to check that too.