So my several month old Prius II has developed a metal on metal sound when I'm hitting various road bumps.. it's a "clack" sound eminating from my wheel well area that is heard when the windows are down.. I've taken it in twice and the first time they couldnt figure it out... second time they said they drove mine and a brand new Prius which also has the same sound and said it was the brake calipers. Funny thing is, I never heard this noise until after about 2k miles on my car.. They also would NOT disable my reverse beep sound or seat belt beep saying it was a safety feature and shouldnt be disabled. Anyone else have this noise on their Prius?