outgoing voice not able to hear !!!!

[MdSaifuddin]

Hey everyone,

In my company network using MGCP protocol with below commands in cisco IOS 15.1

isdn switch-type primary-net5

isdn incoming-voice voice

isdn bind-l3 ccm-manager

The issue is when making an outgoing call the call is connecting and showing the call duration but not able to hear the Voice from both the ends,

But for the incoming call can able to hear the voice from both the ends.Its happening for only one PRI as rest three PRI are working fine with both incoming and outgoing.Plese help me out with this.

Thanks

[Harmit Singh]

Hi there,

Is this PRI terminating on the same MGCP gateway as the other 3 working PRIs? You would need to see if this is a signaling problem or a media problem first and then troubleshoot accordingly. Please upload the following outputs:

show run

show mgcp endpoints

show ccm-manager

Please mention which port the problematic PRI is connected to on the gateway.

Run the following debugs:

debug isdn q931

debug mgcp packets

Capture one bad call with the above debugs enabled. Mention the calling party, called party, IP address of the IP Phone (calling party).

Do you hear a ringback tone before the call connects to the PSTN?

When you have the call connected, run "show call active voice brief" and check to see whether the RX and TX counters are incrementing for the TELE and VOIP leg of the call.

HTH.

--
Regards,
Harmit.

[kstaples]

in addition to Harmit, you'd also want to do your best to set up a packet capture to sniff packets at the gateway to observe if RTP packets are reaching and/or leaving the gateway.

likewise, hitting the "?" mark on the phone when audio isn't present helps to determine in which direction the RTP are flowing or not. you'll see RX or TX incrementing or it may not be, which should help indicate if your sending RTP stream or not receiving RTP streams for the far end.

show call active voice brief will also help to show RTP traffic activity.