Xbox Troubles.....Need some help

[EricCamper]

Hi all....I have chipped a couple of boxes and here are the problems...

The box works great and boots all games....Then every once in a while the box just will not read the discs and says it is dirty or damaged....Then it works fine....I made Splinter Cell 2 and it works great on one box and the other goes to the xbox screen....
I am using the Apple V5 and have never had problems before....Princo 1X media .....burned at 1X.....Now I just got some Riteks and I am going to try reburning a couple of those games that are giving me trouble......This has happened before and I replaced the disc drives with newer ones from a couple of broken boxes.....Where can I purchase them? Which one should I get?
Any help is appreciated..

See ya