Flux TTS is generally available, and is now the default agent voice
By Steven Van ·
Flux TTS is the default agent.speak provider Flux TTS is generally available in the Voice Agent API.
Deepgram announced Flux TTS is generally available, and is now the default agent voice on August 12, 2026.
What changed
Flux TTS is the default agent.speak provider Flux TTS is generally available in the Voice Agent API. A Settings message that omits agent.speak altogether now uses Flux TTS with the flux-kit-en voice, where it previously used aura-asteria-en. Set agent.speak.provider.version to v2 with a flux-{voice}-{language} model to select Flux TTS explicitly, or v1 with an aura-* model for Aura. { "agent": { "speak": { "provider": { "type": "deepgram", "version": "v2", "model": "flux-alexis-en" } } } } The GA voice catalog is 36 English voices across seven accents. See the Flux TTS voice catalog. Breaking: default sessions requesting compressed audio are now rejected Flux TTS streams raw audio, so it accepts only the linear16, mulaw and alaw output encodings, with no container and no bit rate. Because it is now the default provider, a session that omits agent.speak and requests a compressed encoding (mp3, opus, flac, aac) or a container such as wav receives INVALID_SETTINGS where it previously received Aura audio. Name an aura-* model in agent.speak to keep the previous behavior: { "agent": { "speak": { "provider": { "type": "deepgram", "version": "v1", "model": "aura-asteria-en" } } }, "audio"