I can't figure it out. I have a brand new PBA tranny.

We went by the proper procedure to fill the tranny with fluid, 1 qt in the converter, 5 in the pan, feed it 3-4 quarts once the engine is running, etc etc, it has plenty of fluid. The big problem is, when I put it in D, 1, 2, or 3. It makes a very noticable clicking noise, almost like a baseball card in a bike spoke noise. I check all of the drive train and it isn't hitting anything. Here's the kicker, when I put it in reverse, and let the tires spin freely, it doesn't make the noise. It is noticably coming from the transmission, and I have no idea what it is. Ideas?