"victor" wrote in message
I have had this problem drain line electronically rootered several
times from the outside clean out plug, and it clears the line, only to
have it clog up two months later.

What is your guess as to what the problem might be????

The rooter guy is not going to tell you since he has a steady source of
income. Find someone (plumber) with a camera setup and have him take a
look. It may cost a few bucks, but once you see the problem you may be able
to make a permanent fix.