Rattle or knocking in rear passenger side on uneven roads

What is your question?

I have had a persistent rattle that can be heard from the rear passenger side of my car when driving on uneven roads. The noise is the worst between 10 and 40 mph. The entire suspension has been checked and no suspension parts are loose, not is the gas tank or exhaust. The rear shocks and shock mounts are all recently replaced. I have taken it to a dealer who has been unable to locate the source as well. I have driven the vehicle with all trunk lining and spare tire removed as well so that is out of the question.

What makes this problem better or worse?

Driving at speeds between 10-40 mph on uneven or bumpy roads

How long has your 2003 BMW 325i had this problem?

1-2 months