Double audio or audio drops out in LMS

All of our courses have audio narration.  Some courses we put in our LMS will get messed up after doing so.  Slides will have double audio (e.g. slide 8 and 9's audio will play at the same time on slide 8), some slide's audio will drop out all together.  I've noticed that the problem usually occurs with slides in succession (e.g. slide 8 will have slide 8 and 9's audio play at the same time, and slide 9's audio will drop out).

We're at a loss for why this happens or how to fix it.  Sometimes remaking all of the slides fixes it, but that's not a very long term solution.  Has anybody encountered something similar??