M5 SMG shifting noise

[335i/335d?]

Hi all,

I have a friend that has just picked up a M5 E60 with SMG. the car has done about 15.000 miles. He is not familiar with this board and asked me to post his question. He noticed a lot of shifting noise, which seem to come from the cardan. I know that the SMG shifts a bit rougher/louder then the DCT or other normal AT´s, but this seems to me more then standard.
He went to the dealer and they told him that there was indeed more noise then normal but they couldnt find any issues. He went to another BMW dealer and they told him the same. These cars are quite expensive, especially over here in The Netherlands, so the dealers dont have a lot of experience, so I hoped someone on this board can help us with this.

I dont know if this is a known problem, if any body has an idea what it can be and how it can be solved please let me know!

thanks,