### Answer Czech is listed as a supported TTS language for ElevenLabs [(1) ]() , which explains why your bot speaks Czech well. However, the sources don't explicitly list Czech as a supported ASR language with the same level of optimization as major languages. To improve Czech transcription accuracy: 1. Enable Accurate mode – Switch your transcription mode to "optimized for accuracy" rather than speed. This can help with transcription quality. [(2) ]() 2. Use Boosted Keywords – Add Czech domain-specific terms or commonly misheard words as custom keywords (up to 100 supported) to enhance the model's vocabulary. 3. Adjust denoising settings – If background noise is contributing to errors, try different denoising mode settings. Regarding ASR provider selection: The sources indicate Retell uses Deepgram for ASR, but you cannot currently specify your own transcription model. [(3) ]() Note: Retell recently upgraded ASR quality for seven languages (German, French, Italian, Polish, and others) , but Czech was not specifically mentioned in that update. [(4) ]() The multilingual option may be handling Czech through a fallback model rather than a dedicated Czech ASR. For further clarification on official Czech ASR support, you may want to reach out via [Contact Sales]() or check [Retell's GitHub]() .

​ To learn more, see the sources I considered: [[1] Set language for your agent](https://docs.retellai.com/agent/language) [[2] Increase transcription accuracy](https://docs.retellai.com/reliability/wrong-transcript) [[3] Multilingual or Bilingual Transcription](https://discord.com/channels/1186424376300679209/1230269781161279508) [[4] Smarter Understanding, Clearer Calls: Retell’s ASR Just Got a Major Upgrade | Retell AI](https://www.retellai.com/blog/retell-asr) ​

Feel free to tag @AI Evy with additional questions. I also appreciate feedback, it helps me improve.