[Rob_G77]

I've had my Z4 in twice for this to be fixed and the service department don't even know what is causing it. When the car is at highway speed, there's a tinny, metallic rattling sound which sounds like it's coming from the bottom of the car, just behind the passenger seat - or between the seats. The dealership has already checked and not found anything that is loose.

I made a recording of the sound. Please excuse the first few seconds as I try to put the phone behind the passenger seat

Rob

[TheGingerOneNI]

Definitely not the speaker grills? I have a rattle on my nearside which I have narrowed down to the doorcard and when I press on the speaker grill it stops.

[Rob_G77]

I'm wondering if it could be exhaust related? It's a bit annoying to have the constant rattling going on when I'm on the highway.