Comcast customer for 3 years. Was sold the "upgrade" triple play package. Tech knew I had my own modem, but failed to mention that it was not directly compatible with voice service as it does not have telephone port. Instead of canceling service, renting or purchasing an EMTA Modem, I wanted to know if anyone has a recommendation for an EMTA adapter or VoIP adapter that I can plug into my Arris modem that will work with Xfinity voice. Thanks in advance!
I have not seen and do not believe there are any actual eMTA/VOIP adapters to use with Comcast Voice that would plug into one of your cable modems Ethernet ports.
I would suggest first verifying wtih your local Comcast franchise that they do allow customers to own their own voice capable modem and if they allow the use of two cable modems at one location where one is provisioned for internet, your current modem, and the other provisioned for eMTA use for your phone service . If so then you could go to https://mydeviceinfo.xfinity.com/ and input your zip code and internet speed to retrieve a listing of devices that you could use. When the initial screen of devices appears, be sure to check the box to indicate you want to see voice capable devices. If your area is anything like mine, there should be a couple of basic cable modems with eMTA ability listed that you could select from and use in place of an eMTA adapter. You would need to work with Comcast to have this particular cable modem provisioned/activated as an eMTA only device for your phone service. While not a perfect solution you could possibly keep and use the internet modem you have and still be able to use the voice service.
The other, less perfect, way would of course to use the information found in the listing descirbed above to purchase your own cable modem that has both internet and voice capability.