We have installed the following solution:
A remote Router 3825 with an ISDN PRI PSTN Link that connects through the WAN (Dedicated Link) to another 3825 at the local site. On the local site we have a Call Manager 4.2(3), IP IVR 4.0(4) and IPCC 7.2(5). The calls are being routed correctly from the remote site, through the WAN to the IP IVR and the IVR message is heard perfectly, but when the call gets transfered to an agent, there is a loud background noise (heard only by the caller, not the agent), which happens randomly. If the agent puts the call on hold, and resumes it right away, the background noise goes away.
The dial-peer configuration on the remote router are as follows:
dial-peer voice 1000 voip
translation-profile outgoing XXXX
voice-class codec 1
voice-class h323 1
session target ipv4:IP Address of the Call Manager
dtmf-relay cisco-rtp h245-signal h245-alphanumeric
voice class codec 1
codec preference 2 g729br8
codec preference 3 g729r8
voice class h323 1
h225 timeout tcp establish 3
If I disable VAD the background noise is heard only when the agent speaks. Again, if the agent puts the call on hold and resumes, the noise goes away.
Thanks for your support.