We have two phone lines coming to the house... my number and wife's number. When we re-built the house it was wired so that both lines come into each phone jack and our (cordless phones) are 2-line. We plug the cable from the jack into the phone's "Line 1/2" socket. When the phone rings we push "Line 1" or "Line 2" depending on which lights up.
It that going to work with the Arris gateway if I take the phone cable from the wall in my office and plug it into the gateway? There is no documentation I can find on how this all cobbles together on the Xfinity site.
(For my office I'll have to get a simple splitter so I can run one cable to the Arris and one to my office phone.)
The phone cable to the gateway from the Jack has to split the same way as your home lines, and split to the 2 phone ports on the gateway
Are you thinking about someting like this 3-way splitter where I pop this into the wall jack and take L1 to Tel-1 and L2 to Tel-2 on the Arris and plug the office phone into L1/L2? Does that sound right?