Option Explicit
Private Sub Worksheet_Change(ByVal Target As Range)
Dim str As String
If Not Intersect(Target, Me.Range("A3")) Is Nothing Then
With Me.Range("A3")
If IsNumeric(.Value) And .Value > 10 Then
str = "C:\Windows\Media\ringout.wav"
Shell "mplay32.exe /play /close " & str
Else
Exit Sub
End If
End With
End If
End Sub