Can you provide a better description of the sound you're hearing? Does it occur over larger bumps or does it strictly occur from a stop?
From my limited experience some sounds are caused by failed hydraulic spheres in your trunk. If the ride is harsh and stiff over bumps this may be the cause.
If your located near other members maybe someone can listen or suggest a good independent shop to take care of the problem.
02 C32 AMG
84 190E 2.3 5 Spd