Codec Mismatch – How to troubleshoot with CDR Report

We know there are various ways of troubleshooting issues related to codec but how do we troubleshoot if we do have access to CDR Reports only? Well, get the Calling Party Number, Called Party Number, Date and Time of The call. Based on the date and time shared, pull out the CDR Report.

Issue: Call Disconnects immediately as soon as the called party picks up.

Solution: This commonly looks like Codec issue where the negotiation with the codecs are not happening between the calling party and the called party. Now, to have a clear picture, get the CDR Report.

If you see the origCause_value and destCause_value are specified with a value 47 which means Resource unavailable, unspecified and the origCallTerminationOnBehalfOf and destCallTerminationOnBehalfOf are specified with a value of 13 which means Call Control. Even if we look at the the duration of the call which was for 1 second and 5 seconds but the value of  origMediaCap_Bandwidth and destMediaCap_Bandwidth were set to 0 (Zero). If negotiation would have happened properly and for established calls it should have given a value like 64 for G711 or 8 for G729.

Example of G729 call shared below.

The above at least give us a way to see and troubleshoot if there are any issues with Codecs.

Avinash Karnani

I am working in an IT company and having 10+ years of experience into Cisco IP Telephony and Contact Center. I have worked on products like CUCM, CUC, UCCX, CME/CUE, IM&P, Voice Gateways, VG224, Gatekeepers, Attendant Console, Expressway, Mediasense, Asterisk, Microsoft Teams, Zoom etc. I am not an expert but i keep exploring whenever and wherever i can and share whatever i know. You can visit my LinkedIn profile by clicking on the icon below.

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