I have a problem with the disc drive on my 360

At a random point during playing a game (by random point I mean it could be half an hour after I start playing, or it could be 4 hours after I start, doesn't seem to happen any particular time) I can hear a loud click from the disc drive every 2 seconds, then after about 30 seconds of this the game freezes. It isn't scratching the disc so I don't know what's going on. When I play Dead Rising it freezes and gives me a warning that the disc is dirty (it isn't, it's only brand new) and with Saints Row the game just freezes and doesn't give any message. Has this happened to anyone else or has anyone else heard of it happening?
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I am Frank-Zappa-as-imagined-by-the-editor-of-a-famous-rock-&-roll-magazine. I am an anachronism who makes the ugliest music on the planet. I have no right to call myself a member of the human race. I am tasteless, untalented, pompous, arrogant, cruel, insensitive, vulgar and not a fun guy because I don't use drugs.