Hello all! Has anyone ran into the following error while migrating their realtime API code to the latest updates for the session.update client event? Currently connecting over WebSocket: Invalid type for ‘session.audio.input.format’: expected an object, but got a string instead. The API docs show f…

I happened to try something like that yesterday and ended up with the below (after receiving an error about missing rate property as well) for input.format and output.format: format: { type: 'audio/pcm', rate: 24000, }, Oddly this doesn’t match up with what their API Reference docs show, just as…

Realtime API Beta -> Realtime API GA - Receiving type error with session.audio.input.format

API

ianyuhsunlin September 1, 2025, 4:27am 4

Took me a while to realise that the response.audio.delta event has been changed to response.output_audio.delta: https://platform.openai.com/docs/api-reference/realtime_server_events/response/output_audio/delta

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Response.output_audio.delta does not ever get sent via webrtc or websocket

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Realtime API Beta -> Realtime API GA - Receiving type error with session.audio.input.format

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