Fixes to audio attenuation jumps and better sample loop script

Small suggestion: I believe the logic here is supposed to be "if this is another avatar audio and not mine" -- so the better way to write this would be use the getType() you're looking for, not the opposite of that type. Furthermore, we may some day want to support directional injected sources, so maybe we really should change this to be something related to directionality of the source.

Won't hold merge for this change.