I recently installed an 3.5mm aux-in adapter in place of my cd changer, and it appears that bass frequencies through this input are handled more by the various door speakers than by the sub. Is there any setting or filter to route the bass to the subwoofer and the rest of the tones to the door speakers? I fear this may damage my speakers otherwise.

2004 Audi TT Roadster
Concert radio with Bose