Safari: Works fine for this site.
Firefox: Works fine except that it wants to download ALL data before you can start to play content. Gives the impression that things don´t work, but they do. Be patient.
Google Chrome: Acts pretty much like Firefox but also ask the user to give permission to use the QuickTime plugin which is easy to miss (and generally stupid... QT the dangerous carrier of viruses?). So you have to activly confirm the activation of QT before using it, or you will not be able to download any music or video.
Opera: Does not work in the latest version. Downloads content but does not give the play controls for QT.
Explorer: Works ok. It seems though that there are occasional problems with typefaces getting screwed up. If things looks more than usually ”artistic” that is most likely Explorer deciding to go creative.