public static extern uint waveOutSetVolume(int uDeviceID, uint dwVolume);

public static extern uint waveOutSetVolume(IntPtr uDeviceID, uint dwVolume);

Declare Auto Function waveOutSetVolume Lib "winmm.dll" (ByVal uDeviceID As IntPtr, ByVal dwVolume As UInteger) As UInteger

    // retval = waveOutSetVolume(0, &H7FFF7FFF)  ' for both channels, if needed

        WaveNative.waveOutSetVolume(m_WaveOut,volume);

internal static extern int waveOutSetVolume(IntPtr device, int volume);

     set { waveOutSetVolume(IntPtr.Zero, (int)value); }

protected static extern int waveOutSetVolume(IntPtr device, uint volume);

Declare Function waveOutSetVolume Lib "coredll.dll" (ByVal device As IntPtr, ByVal volume As Integer) As Integer

  waveOutSetVolume(IntPtr.Zero, NewVolumeAllChannels);

internal static extern int waveOutSetVolume(IntPtr device, int volume);

     set { waveOutSetVolume(IntPtr.Zero, (int)value); }