Запись звука с микрофона и сохранение в wav - C#

using NAudio;
using NAudio.Wave;
 
WaveIn waveIn;
WaveFileWriter writer;
string outputFilename = "D:/demo.wav";
 
void waveIn_DataAvailable(object sender, WaveInEventArgs e)
{
    writer.WriteData(e.Buffer, 0, e.BytesRecorded);
}
 
void waveIn_RecordingStopped(object sender, EventArgs e)
{
    waveIn.Dispose();
    waveIn = null;
    writer.Close();
    writer = null;
}
 
private void button1_Click(object sender, EventArgs e)
{
    waveIn = new WaveIn();
    waveIn.DeviceNumber = 0;
    waveIn.DataAvailable += waveIn_DataAvailable;
    waveIn.RecordingStopped += new EventHandler(waveIn_RecordingStopped);
    waveIn.WaveFormat = new WaveFormat(44100, 2);
    writer = new WaveFileWriter(outputFilename, waveIn.WaveFormat);
    waveIn.StartRecording();
}
 
private void button2_Click(object sender, EventArgs e)
{
    waveIn.StopRecording();
}