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PSTN users cant hear Call manager users


Im facing a quite intermitten problen when sometimes PSTN calls put on hold and tried to retrive it back PSTN users cant call manager users at all and we have the same situation when answering PSTN external  calls sometimes.Please let me know if anyone else came across this and have solution?

Is that something to do with DSPs?

Thank you


Re: PSTN users cant hear Call manager users

Your message isn't very clear (read it out loud and see if you can understand what you were attempting to say).  I think you're saying you are having a problem picking up calls that were put on hold.

You didn't describe your gateway setup (SIP, H323, MGCP, etc.), but it sounds like you're running out of MTP resources.  You should be able to see this using the RTMT tool and monitoring the MTPs.

Re: PSTN users cant hear Call manager users

Yea True.Thats what happens when you are not focused.

Heres the Scenario

1.When a  PSTN call put on hold and resume it you cant hear anything from PSTN users side but PSTN users can hear you well

2.When a PSTN call transfered to a another extension you cant hear anything but PSTN users can hear you

Please let me know your thought about the issue.Thank you

Re: PSTN users cant hear Call manager users

Are these H323 gateways to the PSTN?


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Re: PSTN users cant hear Call manager users


I hope you are doing great,

I would like to confirm the following information:

Complete topology description:

Can you post a show run of the gateway?

Can you provide a complete version of call manager?

If you are having one way audio issues to the PSTN. depending on the protocol that you are using, do you already doublecheck that the gateway can pingn the IP phones?

Basically as per your notes, at the moment the first call reach the call manager, the call it is connected after that when they put the call on hold they can not retrieve the call?

Can you attach the traces of the CUCM?

Can you provide a more detailed description of the issue?

I will be waiting for this information.


Luis Sandi

Re: PSTN users cant hear Call manager users

Sorry guys coudnt get back to you sooner

Yes it is H323 gateway

This wasnt any issue when resuming calls or forwarding and there wasnt any config changes aswell

I reset the Trunk between call managers today and appearently issue has been resolved now.I tried restarting (not resetting) before which obviously didnt fix the issue

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