Cassiano, thanx for the replay, but sorry, what you say isn't the question I've proposed.
I know how the folder works and how to activate the looping, infact I set properly the loop for the music, loaded in Music folder because I want that it's streamed and the effect in Sound folder for immediate availability.
The game I created works perfectly in the browser: all sounds play, music is correctly in loop, all goes ok.
The problem is only on Android Tablet, when I convert the game in an Android App with PhoneGap and with AppMobi, as I've explained...
Steven