DirectSong

DirectSong is a premium music service that sells extra audio content for Guild Wars.

Their current wares are:
 * Guild Wars Special Edition Soundtrack
 * Battle Pak 1

When the Sorrow's Furnace update came out, the associated music was only available via DirectSong, though it was offered for free.

DirectSong's music is only available as protected (through DRM) WMA files with a bitrate of 128KB/s.