I've been playing games that run from cds, or trying to play cds themselves.  The D drive has started to make the most obnoxious grinding noise - like it's trying to eat the cd - whenever it is used...or thinks it may be used, and then only when a cd is already in the drive.  I'm now afraid to use it since I don't want anything to happen to my computer OR the cds.  So the question is: how do I get this noise to stop?