[LAU] Creative Common License and Rerecordings/Concerts

Hi list, I have a license question, maybe you can help me. A short while ago I released my album "Laute Minne macht dich Hinne" (http://www.wargsang.de/download.php?file=1) under a CC-by-sa license. That means that anyone can do anything with the recordings (for example share, sell or remix them). But what does that mean for the music itself, the composition. If someone now plays one of my songs himself...? Is this covered by the license? Are people allowed or is this a complete different matter? I personally don't think people can play my songs, but I'm not sure. After all the CC-by-sa only means the recording itself, not the musical composition behind it. What do you thin? Nils