All inbound calls from Spanish phone numbers (+34) produce empty transcripts. STT cost is charged but no transcription occurs. Tested with Telnyx and Zadarma (BYO SIP trunk). Audio recording shows noise on user channel. Suspected PCMA (G.711 a-law) being decoded as PCMU. Call IDs: 019e0d85-e33a-7000-89b4-c655b22504e0, 019e0d81-1374-7000-95c0-056f56710f8e

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I can help troubleshoot this. It does sound like a codec mismatch issue likely PCMA (G.711 A-law) being handled as PCMU, especially since +34 carriers commonly use A-law. I can review the SIP/RTP negotiation, codec priority, media handling, and STT pipeline to identify where the audio is getting corrupted. @manusp5

Yeah sure! How do we do it? @Praise Heritage Abayomi

Kindly let's connect @manusp5