Excalliber

I just got duals on my V6 , JBA True Duals with H Pipe. I paid approx 479 plus 185 installed. They look really good. However ... There really seems to be a lot of drone at any Rpm and once in a while I hear a vibration sound . I felt the mufflers and they feel secure so I don't think they are loose or anything. So my question is does the Drone go away ? I have heard people mention that the muffler breaks in and mellows out - any truth to that ?

I also have seen several posts regarding Resonators. Can anyone tell me where to get it and how much it costs to buy / install (if the drone is permanent.

I wasn't looking to make my car too loud and I think the JBA's ar louder than I expected.