Problem here is the changes made dont save. So every power cycle you have adjust the bass and treble againI found this on ClubTouareg somewhere, but can't find the post now:
Not VAG-COM specific, but very helpful For those with the Dynaudio: There is a hidden (or at least not clearly stated) adjustment on the RNS-850 for adjusting the Bass and Treble (not the Individual screen). I was ready to replace my system until I found this. On the menu shown below, if you press around in the middle of screen it will come up with the individual adjustment screen. This appears to be a fine tune screen for the Authentic-Soft-Dynamic-Speech settings separate from the "Individual" screen.