FWIW - to make an audio-book I open the book (normally EPUB, always with no DRM) in Balabolka (Windows), choose a suitable voice, save as MP3, and copy to my MP3 player.
If format shifting between textual formats for personal use is permissible in a given jurisdiction, surely format shifting from a textual to an audible format would be equally permissible.
And, I thought DRM was merely a means to deter breach of the creators IPR, and that its absence doesn't mean a work isn't protected under IPR law.
Apparently Gene Simmons is claiming trademark on a hand gesture
BR