TunesKit Studio has unveiled TunesKit Audible Converter (http://tinyurl.com/zvw4b7k), a DRM cracker for Mac and Windows systems. It can remove DRM from any Audible audio book by converting AA, AAX files to unprotected formats without account authorization.
TunesKit DRM Audible Converter also allows users to choose lossless audio as output by retaining existing parameters like audio codec, channel, bit rate, sample rate, and more. It can strip DRM from audiobooks downloaded from Audible as well as converting existing DRM-locked formats from AA, AAX to common MP3, M4A, M4B, FLAC, AAC, OGG, AIFF, APE, FLAC, WMA, WAV, M4R, MKA, AU, etc. with original metadata, ID3 tags and chapters preserved.
TunesKit Audible Converter is compatible with macOS 10.8 or later. It costs $29.95 for a limited time; a demo is available for download.