You can also use the mciSendString API to play MIDI's, which might be better in your case because you just want ON and OFF features.
Code For module.
Code:
Declare Function mciSendString Lib "winmm.dll" Alias "mciSendStringA" (ByVal lpstrCommand As String, ByVal lpstrReturnString As String, ByVal uReturnLength As Long, ByVal hwndCallback As Long) As Long
To Play the MIDI.
Code:
mciSendString "open C:\MyMidi.mid", 0, 0, 0
mciSendString "play background", 0, 0, 0
To Stop the MIDI
Code:
mciSendString "close background", 0, 0, 0