I have an issue which is mentioned below in details:
ALl Cisco IP phones registered on Cisco Call Manager cluster.
The phones reside on the same local area network,The LAN is a complete Cisco architecture, Layer 3 routing.
The Phones are within the same CCM Region, and assigned with the same Calling Search Space.
If a users on Phone A (ext. 1237) calls a user on Phone B (1238) the connection establishes, however the audio is delayed 6 -10 seconds, in both directions.
The CCM Cluster is located across the WAN, with all the appropriate QOS supporting the IP Phone signalling. There are no VoIP call connections cross the WAN, the voice is all local, calls to and from the PSTN are via the local 3825 router.
Only calls between IP phone to IP phone have the audio delay issue, if any of the local IP phones receives or connects a call via the voice gateway, there is no audio delay.
The Cisco Call Manager service is on version 4.1 (3)sr5b - hardware is MSC-7835 H1
IP phones loads are:
I would be grateful if someone could help me in this issue