[Exwoodchuck]

4/10/12 Edit!

BMW states that it does NOT need to be coded in post 03/09 cars. If you don't code it, the sound EQ is still horribly compressed, the subs are overdriven, and the gong's are WAY too loud (even at min volume).

If you do code it with ISTA/P (or NCSExpert), the gongs/BT voice/PDC/Nav instructions will be WAY too quiet... but the fix is rather simple!

Don't follow the instructions, and especially don't follow the labels on the Crossover... just plug in like-for-like colors on the crossover. They are labeled wrong- so plug your tweeter into the yellow wire out of the crossover, and your mid to the blue wire, matching up the factory wiring colors.

With this, your BT/gong/PDC volumes will be correct!