Transfer case noise present in all X5 models!?!?!?

[autoque]

Took my X5 in for a noise that only occured when I start the car fresh or at least having the ignition off for at least 5 minutes. In a quiet place, putting it in D and very slowly pushing on the accelerator I could hear a distant thunk once in second gear and about 3 to 5 seconds after the gear changes to 3rd. And it never happens again until I put the car away for about 5 minutes and starting again.

The tech said it's present in all X5s and it's the noise that transfer cases make. The tech said when he unplugged the transfer case the noise was gone. The diesel engine was a little louder so it was hard to hear the noise but the 3.0 gasoline model I test drove did have the noise.

The noise is rather noticeable and happens everytime you start and drive the car. I'm surprised that there's no mention of it in this forum of this noise yet. You must all have the noise or is it just me and the test-driven car?