AudioStreamer.cs

using UnityEngine;
using NativeWebSocket;
using System.Collections;

public class AudioStreamer : MonoBehaviour
{
    WebSocket websocket;
    AudioClip micClip;
    const int sampleRate = 16000;

    async void Start()
    {
        websocket = new WebSocket("ws://yourserver:port");

        websocket.OnOpen += () =>
        {
            Debug.Log("Connection open!");
            StartCoroutine(CaptureMic());
        };

        websocket.OnError += (e) => Debug.Log("Error! " + e);
        websocket.OnClose += (e) => Debug.Log("Closed!");

        await websocket.Connect();
    }

    IEnumerator CaptureMic()
    {
        micClip = Microphone.Start(null, true, 1, sampleRate);
        yield return new WaitForSeconds(1);

        float[] samples = new float[micClip.samples];
        micClip.GetData(samples, 0);

        byte[] byteData = FloatArrayToByteArray(samples);
        websocket.Send(byteData);
    }

    byte[] FloatArrayToByteArray(float[] floatArray)
    {
        byte[] byteArray = new byte[floatArray.Length * 4];
        for (int i = 0; i < floatArray.Length; i++)
        {
            byte[] bytes = System.BitConverter.GetBytes(floatArray[i]);
            bytes.CopyTo(byteArray, i * 4);
        }
        return byteArray;
    }

    private async void OnApplicationQuit()
    {
        await websocket.Close();
    }

    void Update()
    {
#if !UNITY_WEBGL || UNITY_EDITOR
        websocket?.DispatchMessageQueue();
#endif
    }
}