Just bought a 19 plate a3 s line

Has subwoofer in boot.all looks factory fitted.

no site of it in settings menu

just treble,bass effects and speed volume

manual says surround and subwoofer section

help!!

Hi Chris,

Did you get this sorted in the end?

I had the same fault and just had it fixed 🙂

This only works for the B&O system. The Audi Sound System does not have (and will not have) that control. 

I've done lots of research myself, due to the smaller power requirements of the Audi Sound System sub, they've not programmed the controls for the sub.

If you have the B&O one, then there is an MMI update (Dealership installed) that brings the Sub controls back to MMI.