[Trooper72]

It is amazing who many rattles the Z4 cabin is generating. I wonder if it has something to do with the fact that the body is too flexible, allowing joints to take impact.

The dealer was using the silicone spray as the cure, but it was a bit like having pain killers for cancer; no lasting effect. After 2-3 weeks the rattles came back.
Now that my car is no longer under warranty (i.e., I need to do it by myself), I have put very thin felt in all joints I can possibly access. But this creaking on the right side of the dash has been a real pain, as evidently I have not yet managed to locate the source of it. This evening I will investigate the airbag and its connection with the dash.

I have been wondering if this car was "made on Monday"... My earlier car, E92 M3, was completely without any creaks or rattles still after 47000 miles of hard driving.
The car before that, E90 335i, only had a creaking sport seat, that was finally fixed after far too many visits to the dealer. After it was fixed, everything was silent.