My harness system uses velcro straps that are help in by sandwiching it between the head and shell. The straps seem to touch the head a little enough to possibly effect the head vibrations. To fix this I've come up with little brackets that are being made now. They are little pieces of lexan shaped to the radius of the shell with a hole in them for the strap to go through. These mount inside the shell to the lug screws and have a little double stick tape on them to prevent them from moving up and down. By using these the straps no longer touch the head thus eliminating the muffle.