By own audio file are you referring to iTunes music? If so, if it has a m4a file extension, with a 99.9999% certainty, you will need to convert that m4a file into .wav in iTunes. The following in the how to link on that. If you need the details customized further, please let us know.
It is easy and quick to do.
This matter has been written about here numerous times. It is not a matter that is unique to version 12.
Always a good idea to look at the tryout version before purchase make sure that the program is compatible with your computer environment and your project goals.
We are not Adobe. Rather user to user. Any questions or need clarification, please do not hesitate to ask.