Publishing in Captivate has slowed

Hello - my Captivate program has slowed so much since I first started publishing recorded powerpoint slide decks. It's simply a powerpoint, with no animations, and recorded audio over it. The latest 'webinar' was 60 minutes and it took an hour to publish. Something like this not even a year ago would have maybe taken 20 minutes to publish at most. Any ideas what is bogging down the program so much?