I have the E- VFT and use the CopperJohn sight you use. I mounted it in the middle holes. The further out you have it the more noize it makes. Where is yours positioned? I heard a tuning fork vibration after shots and figured it was the sight. So I stuck one of the small limb savers (the little guys you put on accesories) on the bottom of the sight. They came in a pack of three so I put one on my MZE. The other one I lost when it flew off of the sight just after application. It vibrated soooo much that I had to use superglue and let it sit over night. Well it was a noticable difference after they where installed! I know you stated that you took components off to look for the noize but I thought I' d share this bit of info with you as you seem to enjoy a quite bow.

Good luck!