mustang1226

So I have been noticing this rattle noise in the passenger side of my dash, actually under my dash more behind the glove box area. I have removed the glove box door, removed the radio and listened to try and tell where its coming from. Finally I had disconnected the climate controls and noticed the rattle was gone. Plug back in the climate control and its starts all over again. It sounds like the blend door or something rattling around in the heater duct system. Could this be the blend door motor? Possibly the blend door its self? Its starting to drive me crazy. It only makes noise over the bumps. Just wondering what your guys think. Also did lots of searching on here with not much luck. Any help would be greatly appreciated. Thanks!