naudio record sound from microphone then save

I'm having some issues with naudio and saving sound recordings. The code I currently have works to the point where it saves the wav file, but when I open it up, Windows Media Player returns an error: "Windows Media Player encountered a problem while playing the file"

I have two buttons, a "Record" button, which turns into the stop button after it's pressed. And I have a "Save" button which when clicked, saves the recording to sample.wav.

NAudio.Wave.WaveIn sourceStream = null;
NAudio.Wave.DirectSoundOut waveOut = null;
NAudio.Wave.WaveFileWriter waveWriter = null;

private void recordButton_Click(object sender, EventArgs e)
{
    int deviceNumber = sourceList.SelectedItems[0].Index;

    sourceStream = new NAudio.Wave.WaveIn();
    sourceStream.DeviceNumber = deviceNumber;
    sourceStream.WaveFormat = new NAudio.Wave.WaveFormat(44100, NAudio.Wave.WaveIn.GetCapabilities(deviceNumber).Channels);

    NAudio.Wave.WaveInProvider waveIn = new NAudio.Wave.WaveInProvider(sourceStream);

    waveOut = new NAudio.Wave.DirectSoundOut();
    waveOut.Init(waveIn);

    sourceStream.StartRecording();
    waveOut.Play();

    recordButton.Visible = false;
    stopRecord.Visible = true;
}

private void saveResponse_Click(object sender, EventArgs e)
{
    int deviceNumber = sourceList.SelectedItems[0].Index;

    string saveLocation = "c:\\wav\\sample.wav";

    sourceStream = new NAudio.Wave.WaveIn();
    sourceStream.DeviceNumber = deviceNumber;
    sourceStream.WaveFormat = new NAudio.Wave.WaveFormat(44100, NAudio.Wave.WaveIn.GetCapabilities(deviceNumber).Channels);

    sourceStream.DataAvailable += new EventHandler<NAudio.Wave.WaveInEventArgs>(sourceStream_DataAvailable);
    waveWriter = new NAudio.Wave.WaveFileWriter(saveLocation, sourceStream.WaveFormat);

    sourceStream.StartRecording();

    MessageBox.Show("Recording successfully saved.");
}

private void sourceStream_DataAvailable(object sender, NAudio.Wave.WaveInEventArg