Welcome to our community, deDogs
If you absolutely must capture the audio using Captivate, you
may need to consider using a patch cable that you connect between
the Speaker out port of your PC and the Microphone or Line In port.
You can buy these at a store such as Radio Shack.
Another alternative is to record the audio separately using
something such as the Freecorder toolbar. Then add it into
Captivate after you have recorded the mouse actions.
Click here to visit
the Freecorder Toolbar site.
Cheers... Rick