If you provide the .mp3 file and make sure it's located in the same location as
your workbook, maybe you could just let windows start up the user's MP3 player.
In the Userform module:
Option Explicit
Private Sub UserForm_Initialize()
Dim myFileName As String
myFileName = ThisWorkbook.Path & "\mymusic.mp3"
ShellExecute 0, "", myFileName, "", "", 0
End Sub
In a general module:
Option Explicit
Declare Function ShellExecute Lib "shell32.dll" Alias "ShellExecuteA" _
(ByVal hwnd As Long, ByVal lpOperation As String, _
ByVal lpFile As String, ByVal lpParameters As String, _
ByVal lpDirectory As String, ByVal nShowCmd As Long) As Long