I had this mate. Posted a few months back. Software glitch I reckon. Still does it once in a blue moon. Scary quiet when it is off! Theres me driving along thinking it sounds the nuts. Only then realising it sounds no different than a fiat cinquento.It only happened a kilometer or so from where i was parking, so it'll need to get it out for a proper drive to see which i prefer. Initial impression was quite good actually, but I'll see better after a proper drive when it's warmed up and I can rev it.