Uh, yeah, if your 360 scratches your discs, there's something not right with your console. Don't stand it up vertically, it happens more that way.
If it's horizontal and it still does it, I wouldn't be surprised if the CD drive breaks on you in the future, especially if it's saying your new discs are unreadable.
It doesn't 'happen all the time'.
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Originally posted by HercMan:
Sounds like corrosion has had it's way with your nuts.