What code-switching is
In many bilingual teams, a single sentence mixes languages: the conversation runs in Persian (Farsi) but technical terms, product names, or code are read aloud in English. This is code-switching, and it is the norm in a lot of engineering and startup meetings — not an edge case.
Why live captions fail on it
Google Meet's live captions are tied to a single selected caption language. Set it to Persian and the English stretches come out as phonetic Persian or vanish; set it to English and the Persian is lost. Meet has no live 'both languages' mode, so a genuinely mixed meeting cannot be captured cleanly by captions alone.
Why many STT engines also fail
You might expect a dedicated speech-to-text service to do better than Meet. Often it does not. In our own benchmarking on real Persian+English meeting audio:
| Engine | Persian↔English code-switching |
|---|---|
| Deepgram (multi) | Excludes Persian from multi-language mode |
| Deepgram (fa) | Mangles the English portions |
| Whisper-class (varies) | Inconsistent on rapid switches |
| Gemini 2.5 / 3.x | Handles it natively — each part as spoken |
The takeaway: 'multilingual' on a spec sheet rarely means 'handles Persian and English in the same sentence.' Code-switching is a specific, harder capability.
How Gemini handles it
Given the recorded audio, Gemini transcribes each span in the language actually spoken — Persian in Persian script, English in English — and can keep an 'English for AI' mode that marks the originally-English speech for downstream agents. Because it sees the whole clip, it also diarizes speakers more consistently than a single-language live caption stream.
This is a post-meeting step, so the practical workflow is: capture live captions for free during the call, record the audio, and run a Gemini pass afterward for the accurate mixed-language transcript.
A practical workflow
- 1.Capture the meeting with live captions for an instant record.
- 2.Record the audio locally (see recording Meet locally).
- 3.Run the Gemini transcription pass for a faithful Persian+English transcript.
- 4.Keep both — the live caption
.txtand the AI transcript — and compare where it matters.