Sentrex1- Teir III tech support with the provider has been working with me. They have come out to the site and monitored the circuit with a protocol analyzer and captured a session (live call) and they say that they are not seeing the Norstar send back the signaling information to generate ringback tone. They have quoted Belcore standard SR4994 ISDN CPE Guidelines Section 5.1 "Audible ringtone shall be provided by the terminating CPE." They said they have looked at all the provisioning and can't find a problem on their end.

I was hoping someone else may have had a problem like this and could give me some insight. Also if anyone is familiar with the 5ESS programming and or 5E and Norstar that they may be able to point me in the right direction when speaking with my provider. I do not know alot about the 5E and I may be using the wrong terminology.