In April this year I bought an audiobook from audible.de and wanted to convert the *.aax file into *.mp3. After some time I found a solution on the Internet, did the convertion and all was good. Till yesterday, when I wanted to repeat the process with another book. Of course I did not remember how to do this... so it took me again some time, but this time I decide to write it down here - for myself and maybe for people with a similar problem.
Step by step guide
Step 1. Download the *.aax file from audible web page.
Step 2. Find out your four activation bytes/auth code.
https://github.com/inAudible-NG/audible-activator.git for that purpose.
Fetch it, follow the instructions (download correct chromedriver, install
selenium and requests packages) and run
./audible-activator.py. It will get your
activation bytes by loging in to the audible (using your credentials).
Save it somewhere, so you don't need to do it again next time.
Step 3. Finally convert it.
./AAXtoMP3.sh <activation bytes> <aax file>.
And that is it. In few minutes/seconds you will have your converted mp3.