Does anyone know of an Xfinity-compatible gigabit modem with built-in telephony but no router/wi-fi? Just about the only Xfinity-compatible product out there with gigabit speed and integrated VoIP seems to be the Arris SURFboard AC-1750, but it's also a dual-band wi-fi router, not to mention expensive and somewhat wonky to set up. Don't need a router or wi-fi; already have a mesh network. Would be great to find something like the Arris SURFboard TM822R but with gigabit capability. Does such an animal exist? Any suggestions much appreciated. Thank you!