Try adding shapes to the slide master named "ding" (they can be invisible - no line transparent fill or just of slide)
As an example use Insert > Action to add a ding sound on click
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You can play this from code
Dim oshp As Shape
Set oshp = ActivePresentation.SlideMaster.Shapes("ding")
oshp.ActionSettings(ppMouseClick).SoundEffect.Play
Should be easy to adapt to If / Then situations