Right-click any audio file on the Library, choose Edit with Adobe Captivate and you'll open the Edit Audio dialog box.
In the image below, parts of the waveform are taller than others. Generally speaking, the taller the wave, the louder the audio. You wouldn't even need to preview the audio shown below to know that the audio suddenly gets louder, softer and then louder again.
Without leaving the Edit Audio dialog box, click the Adjust Volume button to display the Adjust Volume controls. At this point, you'll need to experiment a bit to come up with a volume that sounds the best to you.
If your audio file has multiple sections that are too loud, select Dynamics from the Audio Processing area (as shown below). You can typically leave the Ratio and Threshold settings alone and click the OK button.
In the image below, you can see that the waveform is now pretty smooth (I didn't have to tinker around any further). If your audio still has sections that are too loud, go back and experiment with the Ratio and Threshold sliders to see if you can calm things down a bit.
If there is just a little bit of audio in the waveform that is too loud, and the Dynamics option isn't helping, select the problematic part of the waveform, click the Adjust Volume button and drag the Volume slider down a bit or as necessary to equalize the volume.
Finally, if your audio has sections that are alternating between too loud, perfect and then too soft, try selecting the Normalize option you'll find just above Dynamics. I find that this is the option of last resort and that Dynamics or manual Volume adjustments work better.
Of course, I'd be remiss if I failed to mention that the features you will find in dedicated audio-editing programs like Adobe Soundbooth or Audacity are light-years better than the options you will find in Captivate, but it's nice to know what you can accomplish without leaving Captivate.
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