I made a back quiver following Bud B.'s St. Jude build along. I found that with just leather in the bottom my arrows would slide around and bounce sometimes.
I cut two pieces of carpet out in the shape of the bottom and glued the hard sides together (carpet on the outside). I put that in the bottom and my quiver was nearly silent and all water would run through. For the shafts I glued rabbit fur around the mouth and they stopped shifting and rattling. No sound coming from my quiver at all. Completely silent, so long as I don't rush around. It's well formed to my back and regardless of what arrowhead I use, my arrows don't bounce, rattle, shift, or fall out even when I'm bent over.
I typically have about 11 arrows in my quiver and one broadhead in a stalker quiver on my bow. I usually have three arrows with broadheads, and the rest have blunts. Only things I hear rattle would be some of my tools in my quiver's pouch. I usually stuff a bandana in there and that quiets that.
Hope that helps.