Aluminum noise

Just installed an aluminum driveshaft, now it seems there is clunking from the rear end when shifting (with and without the engine running, regardless if the car is in motion or not).

Does the aluminum shaft amplify rear-end noises?
 
The shaft is new from FRPP. Everything on the suspesion front and back is new, and I had a 3:55 gear put in with the same trac-lok used in the 03 Cobra. The suspension I did myself, the axle I took and had a professional shop do.