One of our customer is using VoIP, on their WAN. There was an AS5300 at the head office to terminate the ISDN PRI, and there are FXS ports on the branch offices. On friday a PS problem occurred on AS5300, and we changed it with an Cisco 3640 with IOS release 12.2(17) with the interface cards NM-HDV+VWIC-MFT-E1. Now the branch offices with 12.0(7)T release can not start VoIP session with this router, but the 3640 can initiate and make VoIP session successfully. On the same WAN I have another 3640+NM-HDV+VWIC-MFT-E1 hardware that these branch offices can start VoIP with this router. Only difference between these two 3640 routers configuration is connection of PRI to PSTN -framing/no framing- setting.
Does anybody have any idea about this situation?
Thanks in advance,