It's all set up and with a system prompt that takes into consideration the proper numeric pronunciation and style to present the information in the Spanish language. Strict direction to speak out in Spanish I see the 11Labs and Azure and others 'supposed best voice interfaces' to fail and mixing up the numbers and some wordings with a strange intermittent language and sometimes english and french. $20.57 is 'veinte (correct)' with fifty seven (incorrect) cents. I tried the most powerful models such as Llama 3.1 & 3.3, came back to GPT 4.1 but nothing... I'd like to line up a troubleshooting ticket with 11Labs in parallel but I don't want to raise a ticket with 10 service providers, it all should be converging here. BTW, using Nova 3 and it works fine (spanish driven)

Try explicitly configuring your Spanish voice settings and enabling text normalization for better number pronunciation. For example, in your assistant's configuration, set the voice provider and ID for Spanish, and enable normalization if supported:

json
"voice": {
  "provider": "azure",
  "voiceId": "es-ES-ElviraNeural",
  "textNormalizationEnabled": true
}

This helps ensure numbers like "$20.57" are pronounced fully in Spanish and reduces language mixing issues. For more details, see the multilingual troubleshooting guide in the documentation you have found. Source: - [Multilingual Configuration Guide](https://docs.vapi.ai/customization/multilingual)

Message marked as helpful by @AlexVendet! 🎉

Still failing: parameter not accepted. { "id": "xxxxxxxx", "orgId": "yyyyyyyy", "name": "Emma", "voice": { "model": "eleven_turbo_v2_5", "speed": 1, "voiceId": "h2cd3gvcqTp3m65Dysk7", "provider": "11labs", "stability": 0.5, "similarityBoost": 0.75, "style": 0.0, "useSpeakerBoost": true, "language": "es", <<< ADDED "textNormalizationEnabled": true <<< ADDED but NOT ACCEPTED }, ----------- { "message": [ "voice.property textNormalizationEnabled should not exist" ], "error": "Bad Request", "statusCode": 400 }

Hey there, we reviewed the details of your request and brought this to our team's attention. We will be getting back to you as soon as we can. Thank you for your continued patience!

I add to move away from 11Labs but still not working well on Azure either. Please advise on other similar cases and possible solutions whether is extra prompting or adding parameters to the models. Thanks, Alex

Instead of using

textNormalizationEnabled

, use

formatPlan

:

{
  "voice": {
    "chunkPlan": {
      "formatPlan": {
        "enabled": true,
        "formattersEnabled": [
          "dollarAmount" // add this one to the list of formatters
        ]
      }
    }
  }
}