I tried the demo and it looks like you have to click Mic, then record your audio, then click "Stop and transcribe" in order to see the result.

Is it possible to rig this up so it really is realtime, displaying the transcription within a second or two of the user saying something out loud?

The Hugging Face server-side demo at https://huggingface.co/spaces/mistralai/Voxtral-Mini-Realtim... manages that, but it's using a much larger (~8.5GB) server-side model running on GPUs.