Hi!! I've got a 106" saw guide that seems to have developed a bow. its about 10 years old and along with other guides I own has been a real hero in my shop! when I place a known straight edge across the raised guide track I get a slight "rock" in the straight edge,which brings about a heavy 1/16" bow in an 8' plywood rip. My question is a) is this a common occurrence in older guides and b) any suggestions on how to fix this?! ( without buying a new guide!) thanks for any help or input!( tried calling Festool a couple of times ,left voice mails with no callbacks)