My car has developed it. Clicks when first moving in either direction and it's getting progressively louder.

 

Nevermind.... found it.

http://www.infinitihelp.com/Ownershi.../ITB05-002.htm

 

I had a clicking sound in mine, after NTB replaced the rear tires with Michelin Pilots. It cost me $100 for the stealership to inform me that one of the nuts INSIDE the wheel holding the valve stem in place had come loose and was bouncing around against the inside of the wheel. I could only hear it at slow speeds, which drove me nuts!