hey guys quick question. i think i have an idea but i figured id ask the pros. from a cold start my flowmaster exhaust sounds like a rattly tin can rice bomb exhaust, but after i drive it down the road and it all warms up, it gets throaty and has that boxer rumble and almost passes for an STi sound. my theory is that the metal just expands and tightens everything up, but im wondering if theres another cause that i can fix, or maybe its a flowmaster thing. ideas??