If you have a published presentation in which audio from multiple slides is playing simultaneously or overlapping, it may indicate that there are PowerPoint shapes (text boxes or objects) in your presentation that have been named with special characters.
You can correct this issue. Here's how:
- Open your presentation in PowerPoint 2007 or 2010, and navigate to the slide where this issue occurs or begins.
- Select the Home tab on the PowerPoint toolbar (ribbon).
- Click on the Select drop-down list (in the Editing group), and choose Selection Pane.
- In the Selection Pane, double-click the names of the shapes that contain special characters (e.g., accent marks, asterisks, quotation marks, etc.), and rename them with alphanumeric characters only.
- Save your presentation, and republish it.
Note that PowerPoint versions prior to 2007 do not include the Selection Pane feature.