Only once have we (Eagle's Flight Archery) had a complaint about our quiver causing the bow to be louder. It was because of the way it was installed, and was easily corrected.
Almost always we hear how our quiver quietened a bow, and how you can't even tell it's on the bow as far as affecting how the bow shoots.
Minuteman, I'd like to make you an offer concerning what you said about, "Never had a bow quiver that didn't make a bow louder. Nature of the beast if you ask me. More stuff to rattle... My $.02" Our quiver (4 arrow) is lightweight, weighing under 6 ounce, and should not make your bow louder, or shoot any differently. If you're interested send me a pm.