We recently installed the UC320W system and are looking to add a second SIP provider as a failover for outbound calls if our primary provider is unreachable. We were looking for an inexpensive option and want to give SIP Affinity a try. I setup an evaluation account with them and have activated a SIP trunk on their end but I'm having trouble with the setup on the UC320W. Has anyone had any success with using this provider? Any tips on how to configure the service?