tts_node:
  ros__parameters:
    voice_path: "/models/piper/en_US-lessac-medium.onnx"
    voice_map_json: "{}"
    default_language: "en"
    sample_rate: 22050
    volume: 1.0
    audio_device: ""              # "" = system default; set to device name if needed
    playback_enabled: true
    publish_audio: false
    sentence_streaming: true