At a BMW CCA car control clinic an instructor's Dinan M3 was ticking. He, and other instructors said it was oil starvation and the lifters were making noise. He was on the skidpad for a while so they think that's what did it. All they did to rememdy this was to park the car and let it sit at idle for 10 minutes or so, don't think it's anything to worry about. But I could be wrong (don't think I am, but I'm saying that just in case I am)