I have an 08 RK with SuperMeg 2-1. I was originally running 20 disks with closed but went to 14 disks and the slotted open billet end cap. I had it dynoed and the bike runs great but there seems to be a buzzing or rattling noise from the pipe which is especially noticeable during idle. It did it both before and after I changed end caps. It is some less noticeable now with the open cap but still there all the same. All the screws are tight.

Is it possible the core/baffles/packing is loose inside the pipe? I find this noise very annoying and takes away from what would otherwise be a great sound out of this pipe. I can't believe this is normal. The pipes are new since March. Any idea?