Private Declare Function Beep Lib "kernel32" _
(ByVal dwFreq As Long, ByVal dwDuration As Long) As Long

Private Sub Command1_Click()
    Dim lngTon As Long
    ' Ausgabe in einer Schleife
    For lngTon = 1000 To 0 Step -100
        DoEvents
        Beep lngTon, 100
    Next lngTon
End Sub