Hi Bruno,
If you are still looking, try this
http://archive.phonetics.ucla.edu There are recordings of many languages. Most are word lists, but there are some story readings too. Also many languages are those you won't find many speakers of in UK or most other countries. Audio quality varies. I have some connected speech from that site and can send you if you like.
Also you can try this site
http://greatlanguagegame.com/
those are conversations from TV programs in various languages. I don't think you can simply download, but maybe the creator of the game will be willing to share.
Cheers,
Valeriy