Incorrect Admin BAr Links

On the home page of http://www.lanuvola.org (wordpress multisite installation with buudypress) drop down menu in the admin bar (top left corner) all links are correct. E.G clicking on "Music" leads to site http://lanuvola.org/music/ . Here now is where the error occurs. When I foolow the link to the music site ... The link for music now is http://lanuvola.org/music/music and for sport the same error http://lanuvola.org/music/sports (The links should always be http://lanuvola.org/sports or http://lanuvola.org/music/ etc

Thanks in advance

Mark M.