RE: Help! My bow is WAY TOO LOUD!
Jeep, a heavier arrow absorbs more of the energy from the bow leaving less of it to vibrate and shock your hand and equipment after the arrow has left the bow. With a really fast bow and really light arrows, it can be like trying to drive a little bitty nail with a massive sledge hammer. The nail will get driven really fast and hard, but your hand and the hammer will end up being jolted pretty hard with all of the left over energy.
Those light arrows, and I use them too, are quite seductive with their flat trajectory and amazing speed, but if you're having problems, the heavier ones can be worth a try.
Honestly though, I have to agree with Rangeball, it's too late to try anything radical now. Give it a shot in the spring.
Keep 'em all in the Bull.