I have the SEL with 8 speaker audio. Does anyone know if the head unit in the Arteons are all the same? In other words, will my SEL head unit have connections for 12 speakers, like what is found in the SEL Premium? I looked below the trunk where the spare tire is ( where the subwoofer is on SEL Premium) but I did't see any wires, so it may not be prewired. If someone has the SEL Premium, could you look at your subwoofer and tell me if it has just the speaker wires (passive sub) or if there's also a power wire (active sub)?