Hvordan ændrer jeg system volumen?

Public Function mciSetVolume(Channel As String, VolValue As Long, sAlias As String)
Dim cmdToDo As String
Dim dwReturn As Long

  If LCase(Channel) = "left" Or LCase(Channel) = "right" Then
    cmdToDo = "setaudio " & sAlias & " " & Channel & " Volume to " & CStr(VolValue * 10)
      Else
    cmdToDo = "setaudio " & sAlias & " Volume to " & CStr(VolValue * 10)
  End If
dwReturn = mciSendString(cmdToDo, 0&, 0&, 0&)
End Function

Public Function mciGetVolume(Channel As String, sAlias As String) As Long
Dim dwReturn As Long
Dim Volume  As String * 128
Dim cmdToDo As String

    If LCase(Channel) = "left" Or LCase(Channel) = "right" Then
      cmdToDo = "status " & sAlias & " " & Channel & " Volume"
        Else
      cmdToDo = "status " & sAlias & " Volume"
    End If
  dwReturn = mciSendString(cmdToDo, Volume, 128, 0&)
mciGetVolume = Val(Volume / 10)
End Function

//>Rune