Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

delayed setup of voice path


I´m having a Callmanager 4.1(3)SR1 with a Cisco 2811 Gateway connected via MGCP (IOS 124-2.T1)

The problem is that sometimes on outbound calls to PSTN have a delayed setup of the voice path. Meaning that the call is already connected but the callers couldn´t hear each other for the first few seconds. It seems to be similar to the problem in H.323 that could be resolved with "h323 faststart".

Is there something similar available with MGCP.

Or any other ideas or experience for this issue??

Thanx for any hint


Cisco Employee

Re: delayed setup of voice path

There are no settings similar to H323 faststart to cut the audio through quicker. Delayed audio with MGCP is typically going to be issues with delays or lost packets in the network. You can look in the Detaled CCM Trace from the server that the MGCP GW is registered to and see if the packets are lost. You will be able to follow the MGCP signaling. If you see something like the below message then the CCM did not see a response from the GW and retransmitted the packet.

MGCPHandler TransId: 328815 Timeout.

You can look at the time stamp of this event and look backwards in the trace for the original signal (look for 328815). I believe by default the timer is set to 3 seconds. So you would have to go back 3 seconds in the trace.

You can adjust the service parameter of "MGCP Timer" to 1 or 2 seconds to decrease the delay in retransmitting the packets if this is the issue. But you probably should look into what is happening on the network.


CreatePlease login to create content