Fixed.
I tested for leaks in the clear pump cover and found it to be okay.
I replaced the pump cover gasket/o-ring ... no change.
I rebuilt the three manual valves: 2 intake and 1 output ... no change.
I rebuilt the electronic valve, which by the way, is rarely used, and THAT was where the problem was. And, it was the last valve I rebuilt. BTW- by rebuilt I mean simply taking the valve apart and changing out 2 small o-rings and 1 larger o-ring per valve.
So, $40 or so later, in o-rings and gaskets, I am good to go with all newly gasketed valves.