as the title suggests, my PS3 has stopped reading its discs. every 1 in 7 tries it will read the disc and i can play, lets say a map of cod 4 mw 2 and then itll just freeze at the end of the map, i restart my ps3 and it no longer detects the disc. any suggestions as to what i can do???? i dont really wanna send it to sony as it costs way too much to repair, so any tips how to get the disc to spin.