I just started to notice the driver's side rear suspension is making "Clunking" noice when the car is over the bumps. I have nothing in the trunk except for the spare and jack. The spare and jack are fastened tightly. I have checked the muffler rubber hanger and it's in good shape. Is it something loose or broken in the suspension? What might be the cause? Is there anyone who have the same problem?

99 E430