audio files blow up my slides when imported.

I'm so far beyond frustrated, I can't begin to express my fury at the amount of time I've wasted on this problem. I am working on a course that's currently about 75 slides long and consists of explainer slides followed by embedded video examples. Narration is required on almost all of them. I used Audacity to create my narration files. When I try to import the .wav (or .mp3) files, certain files blow up the slides, expanding the timeline from 60 seconds or so to 23,000+ seconds, and the audio file never actually loads into the timeline. To recover I have to quit Storyline and restart it without saving my work. I have attempted to embed the audio file in a new slide, and also in a new project. I have re-recorded the audio multiple times only to have the same thing happen no matter what I try, up to and including running the audacity .wav file through an online converter to turn it into an .mp3 file. The file plays fine on iTunes and Audacity, but Storyline chokes on it. And yes, I am one of those poor sods trying to use Storyline on a Mac running Parallels windows emulator. If anyone can figure out how to solve this so I don't have to throw the whole thing out and start over, I'd certainly appreciate. And if there are any Mac users out there who have found a Mac-native alternative, I'd like to hear that too. Because Storyline is way more trouble than it's worth.