Hello everyone! I am a migration specialist currently moving a client from Zendesk Talk to Genesys Cloud. We have set up a new BYOC Cloud trunk with their preferred carrier. The signaling is working perfectly, and calls connect without issue. However, we are experiencing a severe “Unidirectional Audio” problem. The agent can hear the customer perfectly, but the customer hears absolute silence. We have confirmed the agent’s headset and browser settings are correct. Is there a specific SIP header or SDP parameter that usually causes this one-way audio on BYOC Cloud trunks?
The most common culprit for one-way audio where the customer hears nothing is a firewall issue on the carrier side blocking the RTP stream coming from Genesys Cloud. Genesys Cloud uses a very specific, wide range of UDP ports for RTP media (typically 16384 to 32768). If your carrier’s firewall is not configured to allow inbound UDP traffic from the Genesys Cloud media IP addresses for your specific region, the audio packets will be dropped at their edge!
This is a classic NAT traversal nightmare! I manage the APAC region for an Australian enterprise and we fight this constantly. To add to what As noted above, you should also check your “Media Tie” settings. Look at a packet capture and see what IP address Genesys Cloud is putting in the c= (Connection Data) line of the SDP offer. If you have “Media Bypass” enabled but your network cannot route directly to the carrier, the audio will fail. Try forcing the media to anchor on the Genesys Cloud Edges first to see if that resolves the unidirectional issue. It is usually the fastest way to isolate a routing problem!