For what it's worth, I've been trying to source this option from a UK dealer. I've spoken to several dealers and BMW(UK) (BMW Head Office in Bracknell). It would appear the last word on the subject is that it is NOT available within the UK! Which is a shame, because I beleive the uprated front tweaters and rear sub couldn't hurt the sound quality!!! :-(
I have the follwing option codes for anyone who might need them....
The following Option code was supplied by fellow members of this forum and seems to be correct for Europe (excluding UK) and US.
Code 752 Individual Adio System (M Audio)
The following code was originally given to me by BMW(UK) but they later advised me that is was not available. dooh
Code 757 Individual Sound Package
Well it looks like I'm stuck with my DSP system Code 677. Unless anyone knows different.....