I was wondering whether CUCM honors the codec preference list order if a call is setup between two phones in different regions. The scenario uses SIP Early Offer. After the called device presents CUCM with its capable codecs, does the CUCM honor the order of the codec preference list of the calling device or called device. If yes the phone call would use OPUS if not it would use G.722.
Both Phones understand the mentioned codecs.
Region A uses a codec preference list that has e.g. OPUS listed first followed by G.722.
Region B uses a codec preference list that has e.g. G.722 listed first and OPUS listed as second codec choice.
Between Region A and B we have a maximum Audio bitrate of 64 kbps.
If you have configured and correctly associated the regions, there should be only one list to pick from.
Now, remember that if the regions are not defined, it will uses system default for intra and inter region calls. Those settings can be found on: System > Service Parameter > Clusterwide Parameters (System - Location and Region) > Default Audio Codec List between Region