Same happened to me, AO.
And to my daughter, and to several friends whose machines I fix.
I got fed up with the disconnect and other problems at home, and in the end, I sprung the extra cash and bought a Draytek.
I had the occasional dropout with it, and contacted Draytek. They asked me to do some specific tests and send them the results file. The reply was "here is some special firmware code for it, to enable it to work best with the long line length you have."
It's worked flawlessly since then.