Looking for advice on a recurring SIP 408 Request Timeout issue affecting our outbound campaigns routed through Singapore BYOC trunks. The problem manifests specifically during APAC peak hours (0900-1100 SGT) when failover logic attempts to switch from the primary carrier to the secondary.
We have 15 BYOC trunks configured with strict failover ordering via the /api/v2/outbound/campaigns API. While inbound traffic remains stable, outbound calls initiated through Architect flows using the “Make Outbound Call” action fail to register the secondary trunk’s SIP credentials within the 3-second timeout window. The Genesys Cloud logs show a “SIP Transaction Timed Out” error before the failover completes, resulting in a dropped call rather than a retry on the secondary path.
The secondary carrier is a Tier-1 provider with low latency (<20ms) to the Genesys Cloud edge. SIP OPTIONS probes from our PBX show the secondary trunk is registered and healthy. However, the cloud-side failover mechanism seems to drop the session before the 183 Session Progress can be processed by the secondary carrier.
Has anyone encountered similar timing issues with BYOC trunk failover in the APAC region? Are there specific SIP header adjustments or timeout configurations in the trunk settings that can extend the failover window beyond the default behavior?