On Google chrome browser to download the audios click on the Download button and then click on the download arrow 

Download all the audios via Dropbox

To download all the audios so you can play them offline, just click the button below and you will be brought to the Dropbox page, if you don't have the app installed you can download it for free.

It will create a icon on your home screen.

Your password to download the Dropbox files  is :