Originally Posted by jmonier
What the cable actually does is to convert the USB to operate the iPod via its' serial control interface (which is totally different from its' USB interface). Thus all the internal logic that you use via the iPod click wheel, etc. and more is available to the BMW Radio/iDrive.
The cable doesn't speed up the indexing per se. The iPod already has an index of all songs. The 6FL can access this index via the cable and thus doesn't have to do the indexing itself.
The device mentioned by mrbelk does NOT access the serial interface so when used with 6FL it isn't any different than a straight USB cable.
Interesting. It was just a thought; since it's a dock-usb connector + lineout audio. I didn't think there would be any difference. I reckon that little mid-stream "brick" in the 6FL cable _does_ perform some function. I am going to push my CA _hard_ to let me take a cable with me to Germany when I pick up my 335 in May.