Thanks for your answers and ideas, i'll think about all of them but being very fond of music, I looked up websites of music for dogs first.
http://www.music4dogs.com/ happens to be the most interesting. It only offers 2 albums but they are made with original songs especially designed for dogs. I bought the album "relaxation" and just tried it with Keny, it seems to soothe him and besides the music is really nice to listen to :) we had a lovely relaxing moment together (I felt relaxed myself too!) I'll try to find a moment everyday to listen to those tracks and i'll keep you updated ;)