We are trying to setup a Voice VoIP- PSTN gateway based on a Cisco 2600Xm with a NM-2V network module and a VIC-2BRI S/T. IOS is (c2600 – IpvoiceK9-m) version 12.4 (11) XJ-4 Release software. We use a Software end device using SIP and or H323.
We have configured dial peer and the isdn interfaces with commands gleaned from the Cisco website. At the moment we are trying to make outgoing calls from the software end device using SIP via the Cisco gateway to the PSTN via the ISDN BRI voice interface. The call is set-up correctly and the correct dial-peers get used, outbound voice is ok, from the end device to an external phone, but we don’t get voice the other way. A network trace shows only a single RTP stream. Has anyone seen these problems before. I have replaced the NM-2V and VIC modules to eliminate hardware issues, but still have a problems.