Well here's a head scratcher. I was noticing I was getting the phantom well walker hits I've read about. After screwing around with the glass off, ONLY the right ramp entry switch is causing the walker to trigger. To add further confusion to things, it only seems to happen when well walker multiball is about to start (one hit away) or when you are in well walker multiball. If you don't have any or all well walker letters, you can trigger the right ramp entry all day with no walker hits registering. Once well walker multiball is ready, hitting the right ramp entry will trigger a hit and start multiball, and same once you are in multiball - hitting the right ramp entry collects the jackpot if its ready. Once the multiball is over, it's back to normal.
I've swapped the Z connector, adjusted the switch to be less sensitive (although it doesnt register these extra hits all the time, so I'm not sure it needed any adjusting), and reseated the backbox connectors with no real change.
Any idea if there's something stupid I'm overlooking here? I'm at a bit of a loss on what to look at next since the walker hits aren't registering randomly or with regular vibration - it all seems dependent on the right ramp entry switch, but in specific circumstances.
Update: after playing a few games with the glass on, the right ramp entrance switch occasionally triggers a well hit, but not consistently, throughout the game…