As I suspected...I got up this morning to check to see if the auto zero was still working...it is not. So I replaced all the leads from the C25 with shielded wire, ran an earth lead from the chassis to the router table put it all back together and it works again...for the moment. My thinking on the ground from the chassis to the router table is that was the only variable between last night and this morning was when I tested last night the chassis was sitting on the router table (aluminum) so, in theory, the table was grounded to the chassis. If there is a good reason not to do this please let me know.
Thanks again.