I don't have it in audio version, but I downloaded all 4 volumes in PDF format from
www.catholickingdom.com. It was free. Perhaps they have a txt format or other ways to view. I don't recall.
I think I saw it or parts of it in audio format once while looking for other books, but I may be mistaken and I don't recall where I might have seen it. I visit many different sites for books all the time. Just use search engines and maybe you can find an audio version if that's what you're after. It's called "The Mystical City of God" by Ven. Mary of Agreda, translated by Fiscar Morrison.
I can't help you with how to burn a PDF to a CD if you want that. I'd do it by copying the PDF to a Word format and then try to burn a disk, if that would hold even one volume but there's probably a better way. All volumes are very thick, about 2 inches or more. Every page is a treasure! Hope this helps!