What is the key2audio serial code?

The key2audio^TM serial code is a 9 digit code (e.g. A4R-7TH-B9C) which you will find inside of the CD-jewel-case. (Otherwise there is no online solution available for that album.) This serial code is unique for each CD and distinguishes you as a legitimate owner of the CD. You will need this serial code in order to get access to the respective online tracks. Do not share this key code, because this code will work once, only. If you passed this serial code to other users who downloaded the tracks at first, your downloads will not play any more.