I have developed a very weird fault with the inbuilt Sub in my Tourer. Occasionally it will get hooked up on a bass note, i.e. a bass note won't stop. Its like someone is holding down the lowest key on a synth! The problem is fixed by restarting the ICE system or just turning the volume down and back up. I am pretty savvy with audio having made all of my home stereo system, so I intend to get to the bottom of this! Just wondering if anyone else has experienced this or knows a solution! Its a weird one! Cheers - - - Updated - - - Also does anyone know if the Subwoofer is independently amplified or driven by the head unit?