So I'm getting ready to play some good ol' Modern Warfare 2 (Haters gonna hate). Take the disc out of the case, seems normal except for all the minor scratches it has gained over the last year. I have it installed to the hard drive so those scratches aren't a problem. Over time, the disc has gained cracks in the useless plastic part in the very middle of the disc that did no harm either. I put the disc in, it's read by the 360, and I play private match for about 45 minutes. We decide to play online and that's when I get an "unreadable disc" error. I check the disc and it has a crack halfway through it. The 360's on a balanced, flat surface and is laying vertically. I also payed $100 to get this thing repaired about a month ago. I honestly don't know what could of caused this other than the console itself.