the waveOutWrite() and waveOutUnPrepareHeader() functions. The latter is called

When the WHDR_DONE bit sets we can call the waveOutUnPrepareHeader() function to release

    if ((MMRESULT = waveOutUnprepareHeader(waveDevice, waveHdrPtr, Marshal.SizeOf(waveHdr))) != MMSYSERR_NOERROR)

public static extern uint waveOutUnprepareHeader(IntPtr hwo,ref WAVEHDR pwh,uint cbwh);

Declare Function waveOutUnprepareHeader Lib "winmm.dll" (TODO) As TODO

[DllImport ("coredll.dll", EntryPoint="waveOutUnprepareHeader", SetLastError=true)]

public static extern int waveOutUnprepareHeader(IntPtr hwo, byte[] pwh, int cbwh);

[DllImport ("coredll.dll", EntryPoint="waveOutUnprepareHeader", SetLastError=true)]

public static extern int waveOutUnprepareHeader(IntPtr hwo, IntPtr lpHdr, int cbwh);

Declare Function waveOutUnprepareHeader Lib "coredll.dll" (TODO) As TODO