Hi,
Thanks for the heads up on this, I did a bit of searching of the forums after my post and found that several people have had the same symptoms and a drive shaft replacement has cured the problem.
Thought I was hearing things until driving over some rough tarmac 2day and hearing it a lot.
Will call workshop 2moro morning - thank goodness I found a good one I can walk to and took out that Mini extended warranty (as mine expired 1 week ago

)....

- supercharger whine.......supercharger whine.......supercharger whine..
I wonder if they can revoke the extended warranty?
I do love this car, incredible design and a smile on my face every time I drive it but it's just silly how many "little" things constantly need attention..
Is it BMW engineering or where they're assembled I wonder..
Cheers, Geoff.