My door open chime (2001 S430) has changed its sound. Now it sounds more buzzy/rattly like something is loose. Any thoughts? Is this a common prob at 100K miles?
Thanks

It is actually the seat belt buzzer.

All of the audible warning chimes, tones, etc. are generated by the instrument cluster. I don't know of any repair other than replacing the cluster, but that doesn't mean a cheaper alternative doesn't exist. Try getting in touch with http://www.paspeedo.com/

Will this qualify under extended warranty? Can the cluster be pulled and just solder the loose area?