Voice AI NLU Confidence Drop on SG BYOC Trunks

My current config is completely failing as expected regarding Voice AI transcription accuracy.

We are seeing a 15% drop in NLU intent confidence scores specifically for calls routed through our ap-southeast-1 BYOC trunks.

The same Architect flow performs correctly on Genesys-provisioned trunks.

Is there a known codec or latency mismatch affecting the Voice AI service in this region?