Ducking How to Example?

Playing Audio and Have it Fade for Slide Title to be Announced and Back to Audio. Can you direct me to a step by step example to work with Ducking. Thank you

If I understand you correctly you want to talk live to your slideshow, not having a narration track? You have two options: you can either lower the volume manually when playing back the slideshow with the help of the Apple Remote or you can add a silent sound file as a narration track for your title slide and select the “Ducking” option for this audio item.