Can't be saved as macro-free presentation

I just went to save my course in Studio 13 and I'm getting a warning that says the presentation can't be saved as a macro-free presentation and it wont save the course. 

It wants me to go out and do "save as" however every time in the past that I have resaved the course with save as all the audio disappears from the whole course even though its saved in the same place.

Can you tell me what this error is, what it means, why it happened and how to save the project normal or at least not have my audio disappear.

Thanks,