Sometimes on new bows, and even seasoned ones, the screws in the cams can work loose a little. Check to make sure those are tight, hang the bow on a hook, and then tap it. If you don't hear the sound, shoot it and see if that took care of it. If you do hear the sound while tapping it, you should be able to track it down that way. It could be your sight, quiver, or anything else attached to thebow too, so hanging it and tapping is the easiest and quickest way to find it instead of trying to find it while you shoot it.