I just installed the 08 SPT CBE (single tips) today and its really loud and droney. Reading on the forums its almost stock quiet at idle I thought maybe I had a leak. I tried to do a pressure test with a shop vac and it kept blowing out the shop vac hose or my exhaust plug so i think the system is fully sealed. Anything else I should be looking at? Or does the lack of resonator in the mid pipe just make it sound like way?