Audi A6 Active Sound ControlActive Sound (ASU) from Milltek Sport is an innovative solution to enable a user controllable exhaust sound to be made on vehicles that traditionally lack the sound and tone that owners desire; suitable for a wide range of vehicles, the growing range includes Hybrids, EV and diesels. Including 11 selectable sound files, volume, pitch and tone adjustment with user configurable profiles all controlled via Millteks own iPhone or Android app. All our