Apparently the only thing behind the glove box is the air filter. Perhaps we have something back there that vibrates every so often? I'm gonna mess with it over the weekend and see what's back there. I guess you could take it to the dealer but in my case its an intermittent problem so I'm sure I'd hear "could not duplicate problem" after my car had sat at the dealer for a day and that's a day it could get scratched, dinged etc. So I'll DIY it first.

Pat