When the gateway gets no answer supervision from the telco or switch, the guide's fix is voice rtp send-recv. It makes a Cisco IOS gateway open two-way audio as soon as the RTP channel opens, without waiting for Connect.

Checked 2026-09-24

Vendor
Cisco
Product
Cisco IOS voice gateways
Subsystem
answer supervision
Deployment
on-premises
Region
not restricted
Release range
Unified CM 12.5(1) guide
Checked
2026-09-24

Sources

Cite this note

APA

WarmTransfer. (2026, September 24). One-way and no-way audio diagnosis: source note one-way-audio-voice-rtp-send-recv. WarmTransfer. https://warmtransfer.net/knowledge/claims/one-way-audio-voice-rtp-send-recv

BibTeX

@misc{warmtransfer-claim-one-way-audio-voice-rtp-send-recv,
  title  = {One-way and no-way audio diagnosis: source note one-way-audio-voice-rtp-send-recv},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/one-way-audio-voice-rtp-send-recv},
  note   = {Source note one-way-audio-voice-rtp-send-recv, checked 2026-09-24}
}

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