|0||Header code [0x00150082]|
|4||Event handle (0 = unregister the event that was previous registered)|
|0||Header code [0x00150040]|
Application should unregister the event by setting handle to zero. If the session was closed before the event was unregistered, it will cause a handle leak in DSP process.
DSP can hold up to 6 concurrent registrations. More than that will cause registration to fail.