It is a loud "clunk". Not the same noise when your pads are sticking to wet rotors. I have had the same problem for the last 14k miles. It is definately very intermittent. I am taking it to the dealer to look at my synchros and I will have them look at it. As far as I can tell, for now, it is not causing a problem. Still want to know what it is.

 

I think you solved the problem about the pads sticking cause i do wash my car every night before i put it in the garage