I think my problem is solved. I bit the bullet and went under my
house (crawl space) this PM, and found some 4" water!
Seems my pressure tank's pressure valve/gauge was acting like a water
pump, spewing water everywhere. Why this did not trip the breaker I
don't know! God knows how long that has been going on. I replaced
the valve/gauge, and evacuated most of the water with his sump pump,
It probably will take several days to dry out under there! Almost
immediately the phone buzzing stopped. Now the phones are all fine.
They must have been submerged.

Now I have to put all the phone face plates etc back in place, not to
mention all the furniture. Wife is talking divorce.

Thanks ALL!

Jethro