To record audio:
From the Insert tab, click the Audio drop-down arrow, then select Record Audio.
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Type a name for the audio recording if you want.
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Click the Record button to start recording.
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When you're finished recording, click the Stop button.
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To preview your recording, click the Play button.
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When you're done, click OK. The audio file will be inserted into the slide.
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Working with audio
To preview an audio file, Click an audio file to select it.
Click the Play/Pause button below the audio file. The sound will begin playing, and the timeline next to the Play/Pause button will advance.
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To jump to a different part of the file, click anywhere on the timeline.
To move an audio file:
Click and drag to move an audio file to a new location on a slide.
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To delete an audio file:
Select the audio file you want to delete, then press the Backspace or Delete key on your keyboard.