O.k.... I just got a call from my brother.
He has figured out and solved the problem, and the answer was nothing I would have ever come up with. He kept thinking the problem had to have something to do with the pugmill--- and I kept telling him that didn't make any sense. Well, he adjusted the speed of the augers and the clay is now coming out perfectly again.
I don't know how or why, but there ya have it.
Thanks again to all of you for taking the time to respond.