Take it to the dealer. If its a common one they will be able to fix it fairly quickly. I have a rattle at the front and in the back so I booked myself an appointment. I'm not wasting my time sorting it ..... this is what the warentee that costs so much to keep hold of (ie Works kit) is for
Hubby has an 03 Cooper S with a really irritating rattling dash. It's been into the dealers 3 times now and each time they state they have sorted it but each time they haven't. Now it's over a year old the rattle has got even worse! Its frustrating and the problem is forcing an early trade in for a newer MINI that's (hopefully) blissfully rattle free!