I am trying to set up callcentric on Sip 2 (eventually, I want to set up Callcentric on both sip1 and sip 2). I followed callcentric's instructions and the instructions here, and I'm still getting an error that says "Backing Off (8665): Authentication Error." I have two DID's in my call centric account, and I don't see in the instructions where it would tell CC which number to use. I've tried changing the SIP Password, using the AuthUserName both with and without the extension. Can't authenticate. Help appreciated.