Jeffrey,

My E320 (97) does the same occasionally, I think it's just the sunroof cover (shade?) jiggling...doesn't sound like that, but when I push it snug, closed, it stops.

__________________
Jeff

97 E320, ours 217,000miles
91 190E 2.6 daily driver 242,000miles
74 MGB,mine 120,000?
2006 BE350/Proline 21, 50 hours