You want to delete sounds added with Record Narration or otherwise from the presentation.
Solution
Run this macro to delete sounds from your presentation file. We suggest running it only on a COPY of any important presentation.
Sub RemoveSounds()
Dim oSl as Slide
Dim oSh as Shape
Dim x as Long
For Each oSl in ActivePresentation.Slides
For x = oSl.Shapes.Count to 1 Step -1
Set oSh = oSl.Shapes(x)
if oSh.Type = msoMedia Then
If oSh.MediaType = ppMediaTypeSound Then
osh.Delete
End If
End If
Next
Next
End Sub