Installed the MAP Testpipe and Catback and noticed that when I'm driving upon deceleration I hear a crinkling or dragging sound from the exhaust it's really annoying. The exhaust is far from the ground, the bolt are tight and the flanges in place. Any suggestions.

 

video of the noise would help. It doesn't run anywhere near the driveshaft right?

 

could be some heatshield vibration somewhere under there