Sony crx300e problem

my sony crx300e will work properly with authentic dvds and cds e.g. Windows xp CD. But when I insert a copied CD of files it will not show up the files or it will not open the files or even let me copy them and paste them onto the hard drive. Also when I insert a copied music CD, the audio is totally distorted and keeps skipping. Does anyone know what could be wrong with my CD drive or has anyone come across this problem with their Sony CRX300e? I would be grateful for any advice or replies, thanks!

-Moved to Recording Hardware forum-

Maybe the discs were not copied properly.