AUG HBAR

Alright, well ever since I've been playing around in this very glitchy speed lobby my MW2 Disc has been acting a little strange, Like it start saying the disc was unreadable. I have tryed just about everything, you can name anything to try to clean it, and I probably tryed it and it still does not work. I've even took it to this store where they surface the disc and it still says it is unreadable. Can anyone please help me out here? I don't really want to spend another 40-50$ on another disc..