{"record":{"id":"1185a314b442e74c","repo":"BerriAI/litellm","slug":"unsupported-audio-format-for-gemini-tts-models-a","errorCode":null,"errorMessage":"Unsupported audio format for Gemini TTS models: {audio_format}. Gemini TTS models only support 'pcm16' format as they return audio data in L16 PCM format. Please set audio format to 'pcm16'.","messagePattern":"Unsupported audio format for Gemini TTS models: (.+?)\\. Gemini TTS models only support 'pcm16' format as they return audio data in L16 PCM format\\. Please set audio format to 'pcm16'\\.","errorType":"validation","errorClass":"ValueError","httpStatus":null,"severity":"error","filePath":"litellm/llms/vertex_ai/gemini/vertex_and_google_ai_studio_gemini.py","lineNumber":1026,"sourceCode":"        speechConfig = {\n            voiceConfig: {\n                prebuiltVoiceConfig: {\n                    voiceName: \"alloy\",\n                }\n            },\n            languageCode: \"en-US\",\n        }\n        \"\"\"\n        from litellm.types.llms.vertex_ai import (\n            PrebuiltVoiceConfig,\n            SpeechConfig,\n            VoiceConfig,\n        )\n\n        # Validate audio format - Gemini TTS only supports pcm16\n        audio_format: Final = value.get(\"format\")\n        if audio_format is not None and audio_format != \"pcm16\":\n            raise ValueError(\n                f\"Unsupported audio format for Gemini TTS models: {audio_format}. \"\n                f\"Gemini TTS models only support 'pcm16' format as they return audio data in L16 PCM format. \"\n                f\"Please set audio format to 'pcm16'.\"\n            )\n\n        # Map OpenAI audio parameter to Gemini speech config\n        speech_config: Final[SpeechConfig] = {}\n\n        if \"voice\" in value:\n            prebuilt_voice_config: Final[PrebuiltVoiceConfig] = {\"voiceName\": value[\"voice\"]}\n            voice_config: Final[VoiceConfig] = {\"prebuiltVoiceConfig\": prebuilt_voice_config}\n            speech_config[\"voiceConfig\"] = voice_config\n\n        if \"language_code\" in value:\n            speech_config[\"languageCode\"] = value[\"language_code\"]\n\n        return cast(dict, speech_config)\n","sourceCodeStart":1008,"sourceCodeEnd":1044,"githubUrl":"https://github.com/BerriAI/litellm/blob/77b7c6c40c0c5aa5fbcb1d6a1825ac39ca8829b8/litellm/llms/vertex_ai/gemini/vertex_and_google_ai_studio_gemini.py#L1008-L1044","documentation":"Error \"Unsupported audio format for Gemini TTS models: {audio_format}. Gemini TTS models only support 'pcm16' format as they return audio data in L16 PCM format. Please set audio format to 'pcm16'.\" thrown in BerriAI/litellm.","triggerScenarios":"Triggered when an audio format other than 'pcm16' is requested for Gemini TTS models.","commonSituations":"See trigger scenarios.","solutions":["Set audio format to 'pcm16' for Gemini TTS models."],"exampleFix":"litellm.speech(..., response_format=\"pcm16\")  # audio format pcm16","handlingStrategy":"validation","validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"77b7c6c40c0c5aa5fbcb1d6a1825ac39ca8829b8","analyzedAt":"2026-08-18T11:44:31.656Z","contentChangedAt":null,"schemaVersion":2},"datasetVersion":"2026-09-14T05:17:10.506Z"}