Source note · One-way and no-way audio diagnosis
For the opposite case, where the PBX user hears the PSTN party but not vice versa, Twilio gives three causes: a firewall blocking RTP from the PBX to Twilio, the internet provider filtering RTP, and routing that brings the packets' TTL down to 10 or less.
Checked 2026-09-24
- Vendor
- Twilio
- Product
- Elastic SIP Trunking
- Subsystem
- media path
- Deployment
- multi-tenant
- Region
- not restricted
- Release range
- current as of 2026-09-24
- Checked
- 2026-09-24
Sources
- Troubleshooting your Trunk — Twilio · tier 2 current vendor documentation · Heading: The person on your PBX can hear the person on the PSTN end of the call, but not vice-versa
Cite this note
APA
WarmTransfer. (2026, September 24). One-way and no-way audio diagnosis: source note one-way-audio-twilio-pbx-rtp-blocked-outbound. WarmTransfer. https://warmtransfer.net/knowledge/claims/one-way-audio-twilio-pbx-rtp-blocked-outbound
BibTeX
@misc{warmtransfer-claim-one-way-audio-twilio-pbx-rtp-blocked-outbound,
title = {One-way and no-way audio diagnosis: source note one-way-audio-twilio-pbx-rtp-blocked-outbound},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/one-way-audio-twilio-pbx-rtp-blocked-outbound},
note = {Source note one-way-audio-twilio-pbx-rtp-blocked-outbound, checked 2026-09-24}
}