A recent trouble ticket with callcentric resulted in them recommending I change the following. I am wondering if it is appropriate for the default configuration to make this change as well.
"Also, from the configurations that you have provided; can you log into the ITSP Profile configuration page and set "callcentric.com" as the "RegistrarServer". After applying the change above, you may need to reboot the device in order for the change to take into effect. "