Backup copy of crash team racing sticks

[gabdes]

I have just backup a copy of crash team racing using CDRWIN4.0 and the patch for this game. Mod chip is installed in playstation and seems OK. Game loads up to the point where the game is about to start and freezes up. If i use the original disc and get the game loaded then swap the disc over to the backup I can quit and reload without any problem. the problem arises again when I switch off the unit and turn it back on. Any suggestions what I might have done wrong ?