12 Bolt Auburn Posi Backlash

Hey there gear heads... been hearing, and feeling these noises that come from the rear...binding and pressure release type sounds, kinda slam bang when put into gear and sometimes when gears change from 1-2 or 2-3, just hear this sound in the rear end...take the cover off the rear drain the greeze...and notice that there is a lot of back slap, this posi was installed professionally by GM and has 10 000 miles on it, should I expect this kind of wear and tear on the rear in this short a time? Check out my Vid I posted on Youtube....>>> Pinion Ring Gear Mesh Noise Identified Looking for advice in Youtube Land - YouTube Attachment 61367

I know.. Old post but,that is not a auburn posi carrier! "backlash" is between ring and pinion only. I use .008 to .010 for backlash unless its a AAM brand gear set. Need to tear the diff down and find the source excessive clunk.