Quoted from ChrisHibler:Not a switch matrix issue.
Either the spoon switch is too closely adjusted or the pop bumper Driver Board has an issue. Perhaps fractured solder joints at the header.
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Chris Hibler - CARGPB #31
Http://chrishiblerpinball.com/contact
http://www.PinWiki.com/ - The new place for pinball repair info
Reflow the pins on the pop bumper boards, notorious for cracked joints which cause all sorts of havoc.