Outbound calls ringing not connecting - no codec - location issue?

[CUCM55120]

We have CUCM 12.5.1 including IM&P servers and Jabber users. We have an internal extension support number users can dial which translates to an external PSTN number at a cloud contact centre provider (likely on SIP as well). We have SIP trunks to our ITSP for outbound PSTN calls.

We have noticed when calling from Jabber devices that are configured on CUCM with Location X the call connects and the cloud contact centre auto answers as expected and begins the IVR. If the Jabber device is configured with Location Y the call just rings out. I have checked the config for each Location and while there were some differences I have configured both to match each other (no restrictions between locations) but it still behaves the same.

Looking at call logs no codec is selected so I am guessing it is an issue with the codec or media termination but I am unsure how this relates back to the Location configuration. I understand Location configuration is assigned to things other than phones such as Trunks etc so I assume it must be that the Location setting that works is assigned to another device or object that is in the call flow or something along those lines?

Thanks.

[Roger Kallberg]

The problem is not very likely to be related to Locations, it’s more likely to be related to Regions. A location sets the bandwidth that can be used for calls between locations and a region sets the max bandwidth per call that can be used for calls between regions. The region influences what codecs that are available for use as the max BW per call match the needed BW for a specific codec. So if the max BW per call is less than what is needed for a specific codec that would equate to it not being eligible for use.

[Dmytro Benda]

Can you please provide the screenshots for Location X, Location Y configs, phone config and SIP Trunk config (to your cloud)? It is hard to advise you something not seeing actual configuration.

As Roger mentioned in his reply, your problem may be not related to Location settings at all. Location config in CUCM just check the available bandwidth between two Locations. If you exceed the allowed bandwidth, the call fails (the call is not permitted by the CUCM in this case). So it is strange, that your call rings out at all. 

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