Sorry for the delay but I have been travelling and progress on this matter delayed. So after my previous post wher the issue seemed to be fixed I drove the car about 100km and left it in my garage while away for 2 weeks. Came back and noises were there again. Not happy so booked car back in. yesterday the dealer applied Teflon tape to the inner rubber seals - those that sit in the door cavity not those on the door. This was the latest thinking from Bavaria.
So far about 200km travelled and no noises.
My next step will be to write a letter to state that the Teflon tape is essentially a workaround to the underlying issue and to ask how BMW might determine a long term fix. My concern is that the Teflon tape may peel over time and we are back to square one. There seems to be enough noise around on this issue that one hopes they formulate a real fix. One of the dealership staff has also had this problem.