If you are just starting out in Audiobook Narration through ACX and you are about to submit an audition, a sample, or your completed audiobook and you freeze and begin to doubt whether your formatting is compliant with their standards. I've been there, I get it. When I first started out, I had to watch dozens of Youtube videos and researched ACX's submission requirements, and conducted so many hours of trial and error to find the right formatting functions.
But now, ACX has introduced Audio Lab, a tool that analyzes your files for their standards of compliance BEFORE you submit your audiobook files, samples or auditions. Check it out here: https://www.acx.com/audiolab. This is a game-changer. I had homemade analytic tools made by other narrators that I had used to help find my right formatting steps but I never really liked the fact that I didn't really know what I was downloading onto my computer. I mean, really, you have got to be careful these days. But this tool is provided directly by ACX and is designed to tell you what you need to tweak to be compliant with their standards.
So, if you are ever in doubt, upload your file into this online tool and double-check before you submit them and 30 days later, QA has kicked the files back to you for some formatting error, saving you and your Right Holder so much time. Good Luck and have fun!