Single clicking noise in axle area

[inca99]

Hello, I recently purchased a 2008 XC90 V8 with 95K miles. Great car, very nice condition, but I am concerned about a clicking noise that I hear in or around the transaxle underneath. The sound is similar to if you tapped 2 pieces of metal together one time. Seems to only present with the application and release of torque. Throttle on, I hear 1 click, coast, another click. Also when I'm coasting to a rolling stop and the gears shift up to say...1st from 5th, I can hear 1 click. It does not effect the way it drives, but I've never had a car that does this, so I don't think it's normal. (My indie said it was normal, but I don't think so.) Any thoughts or similar experiences would be appreciated! [It is also present when shifting from back and forth from D to N to R while stationary.]