I don't have an '18, but I have heard of some people having problems with their active exhaust. The problem you described is they say it starts, then it progressively gets worse where the message won't go away and they can't adjust the settings. Do you have your "quiet mode" setup for a certain time of day? Some people have said when they park their car in normal mode, and then start their car up during the quiet mode time, they can tell the exhaust is still in normal mode. Get in the car, see the message, then the message goes away and the exhaust switches to quiet mode like it should have. So far the dealers seem to be taking care of the issue.