Adding closed captions to a slide is relatively simple. Choose Audio > Audio Management to open the Advanced Audio Management dialog box. Select a slide that contains audio and, at the bottom of the dialog box, click the Closed Caption button. From there, click where you want the closed caption, click the Add Closed Caption button (the plus sign) and type the caption.

It really is a simple process… labor intensive, but simple. If you have several slides with audio, you'll need several closed captions, which will take time. But seeing how you are determined to add closed captions to your project, you work and work and work and then, one day…success… your project has hundreds of closed captions. Congratulations are in order!
And then your world falls apart… the client requests that the audio on several slides be replaced with new audio. You honor the request only to realize, with absolute horror, that the closed captions for the replaced audio clips have been deleted and now you'll have to recreate the missing closed captions. Unless…
If you need to replace a slide's audio clip, you have two choices. First, you could choose Audio > Import to > Slide and replace the existing audio clip with the new one. This sounds like the most straightforward method. However, if you proceed, you will lose the slide's closed captions (sort of like throwing out the baby with the bath water). Instead, choose Audio > Edit > Slide. Select the waveform via the Edit tab and replace it by either clicking the Import button or the Library button. Once the audio has been replaced, check out the Closed Captions tab and you'll see that the captions have been retained. Nice!
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