Rattling Noise

when i'm going at a slow speed (25-35mph).. i hear rattling sound where the seatbelt comes out.. anyone have this problem?

I get a sound like marbles rolling aroud in that area at low speed. Sometimes it drives me nuts. Couldn't find anything loose, but I haven't taken the molding off. I think it has to do with the body flexing.

i think every car has this problem, once the cars rpm hits a certain point and produces a certain frequency it just likes to jiggle crap around, my brothers does it at about 3200 rpm.........my passenger side visor does it at 1700.......just gotta find whatever it is and tighten it up......