Unified CM picks a call leg's audio codec by taking the codecs both sides support, removing those above the region's maximum audio bit rate, and then choosing the most preferred remaining codec from the audio codec preference list.

Checked 2026-09-25

Vendor
Cisco
Product
Unified Communications Manager
Subsystem
regions
Deployment
on-premises, dedicated-instance
Region
not restricted
Release range
15 and SUs
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). SIP 488 and codec negotiation failures: source note sip-488-codec-failures-cucm-codec-selection. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-488-codec-failures-cucm-codec-selection

BibTeX

@misc{warmtransfer-claim-sip-488-codec-failures-cucm-codec-selection,
  title  = {SIP 488 and codec negotiation failures: source note sip-488-codec-failures-cucm-codec-selection},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-488-codec-failures-cucm-codec-selection},
  note   = {Source note sip-488-codec-failures-cucm-codec-selection, checked 2026-09-25}
}

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