I purchased a Milltek Exhaust system for my A4 2,8 V6 quattro, its a quality product, but I have a problem with the Milltek front section where it meets the two pipes from the cat, On the original system the pipes are the same diameter and both sides, connect with a sleeve. But with the Milltek the front section is bigger, a flange (it fits over the original pipes from the cat) and connected via a clamp. The problem I have is there is a small blowing from these two connections. Has anyone had this problem & how to fix it? Should I try fitting the sleeves over these flange joints?