I've been following this forum for a while now, and I haven't seen any discussion on the ASC feature of the radio. (I have the 'upgraded' radio in the S60 AWD, MY2002.) I'm curious how it is supposed to function, since I have not noticed a difference in sound as the interior noise level changes. (I still have to turn up the radio on the highway and down when I'm in town.) I asked the dealer about this today and he said the change would be so subtle that I wouldn't notice it. Thus my obvious question: What is the purpose of the ASC if it is not noticable?