Microsoft response code 531027 with SIP 488 ('There are no ICE candidates in the SDP') means media bypass failed because the SBC's SDP had no ICE candidates. Microsoft's fix is to enable ICE Lite on the SBC.

Checked 2026-09-25

Vendor
Microsoft
Product
Microsoft Teams Phone Direct Routing
Subsystem
media-bypass
Deployment
multi-tenant
Region
not restricted
Release range
current as of 2026-09-25
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Troubleshooting Teams Direct Routing: source note teams-direct-routing-troubleshooting-488-ice-lite. WarmTransfer. https://warmtransfer.net/knowledge/claims/teams-direct-routing-troubleshooting-488-ice-lite

BibTeX

@misc{warmtransfer-claim-teams-direct-routing-troubleshooting-488-ice-lite,
  title  = {Troubleshooting Teams Direct Routing: source note teams-direct-routing-troubleshooting-488-ice-lite},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/teams-direct-routing-troubleshooting-488-ice-lite},
  note   = {Source note teams-direct-routing-troubleshooting-488-ice-lite, checked 2026-09-25}
}

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