since I have voice service, I can't replace the gateway with my own equipment
If you have Cox Voice (landline), Cox must freely loan you a standalone telephone modem (eMTA). Just because Cox bolts a DOCSIS and WiFi onto an eMTA, Cox can't mandate you rent the combo unit for Voice service. When you close your service, however, you'll have to return the standalone or pay for it.
You'll then have 2 modems. One for Voice and another for Internet. You'll just need to install a coaxial splitter at the Primary Feed...probably in your Living Room...to connect both modems.
You do not need the Panoramic. You can return it, get the standalone, purchase a DOCSIS and install your CM1200.
As far as previously registered, you can resolve this via email to cox.help@cox.com.
