Hi justaerin! Well...not to worry! We're not all genius's on here! (Some guys come pretty close though, I believe!). The XB engine IS inheritally noisy....you've got 4 cams in there, all TRYING to go their own direction, 4 pushrods and rocker arms that are sitting up there on top. Are you riding with say...a different helmet, or the visor up? Anything different that would make it SEEM to sound different? I know...that seems too easy, but its a thought! After that, without really hearing it, the door is pretty wide open! Has it got a different exhaust than stock? Jardines need re- packed...especially if you have a lot of decell pop going on. A broken baffle in a stock type exhaust would make noise. I have no experience with the interactive exhaust valve...perhaps someone here could give you some pointers on that. (IF you're still running it...many aftermarket exhausts eliminate it). Sorry...not much help, but its the best I can do for now!!:)