I had a similar problem some time ago. In a hurry, I placed a DVD in the tray; and didn't notice that the DVD was not fully inside the tray (inside the insert of the tray). So the DVD got stuck; the only way to remove it was to open the RT210 by removing the screws located at the back of the unit.
You should never use a disc thats scratched inside yiour machine its most likely your dvd machine is having trouble reading your media the best way to solve this is to unplug your machine wait turn it back on keep pressing eject it should eject dont use that dvd disc again hope this solves your problem did for me ;
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