HD Installing Audible on Kindle Fire HD 5.6.0.1

Hi,
I do not have Audible on my Fire HD 5
I have tried many solutions from the web even to install Google Play etc.
But no all I get is an error 505 code.
I have exhausted every conceivable method of overcoming error 505 code.
But no, still error 505 code.
I can install other apps from Google Play but Audible always gives me a error 505 code.

:help:

Am I the only nerd on :smack: this planet who cannot get Audible on his Kindle HD 5.6.0.1? Please and pretty please, can some kind person tell me how to install and enable Audible on my Kindle?????

Thanks and kind regards, :thanks:
jB :cool: