[trifest]

So I had an Akrapovic exhaust installed about 4 years ago when I bought my M6GC and it's been great. Lately I've developed this tinny rattle noise when decelerating around 1800 rpms as the revs come down. on a downhill where I can hold the rpm, I can sustain the noise for longer than a split second and especially if there's a wall it'll sound absolutely horrible. Dealer checked heat shields but didn't see anything. Could it be the cats going bad? It seems to be more forward than towards the rear and mufflers.

seems to be more prominent when the exhaust is warmed up and is kind of muted when the car is cold especially right now in the winter. Thanks for the help!