Does anyone have the Quiet Core insert for their e-series? I have an WB e-series muffler and it seems a bit loud. I know that pipes are generally loud, but this seems a little excessive. I read that these pipes are among the quieter ones so I'm thinking maybe I just need to re-pack it. How long does muffler packing usually last? I bought this quad used so I do not know how old the pipe is.