Agents
Only the Owner or a calling manager can change calling settings.
Calling agents
Calls ring each user on the phone number in their profile, so every user who takes calls needs one. With TeleCMI, an Owner can also turn on VoIP for a user: the app creates the user's TeleCMI agent and calls then ring in the browser.
TeleCMI is not set up yet, so VoIP cannot be turned on. Add it in Calling > Providers.