In the back of your CDrom you can set it jumpers for either:
1. Master
2. Slave
3. Auto
If you currently have it set for auto then change it to one of the other manual settings. There should be a small reference on the sticker on the CDrom as to which jumper is for master and which one is for slave. Sometimes there are also letters like MS and SL on the plastic near the CDrom jumpers. If you can't get the settings from any of those things then you should be able to go the website for your CDrom and look for jumper settings there (like Liteon.com).
BTW the jumpers I am reffering to are the ones on the back of your CDrom and not the ones on your motherboard.
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