Locked dvd tray.

The open/close button will not open the dvd tray and a "locked" message appears in the window.
I have a 3 drawer cd player. LED's come on, but no drawers will come out, or will it play the tracks of a cd that appears to be locked into the drawer. Power on and off does not fix the problem...I have owned an RSQ MV 333 identical to this one and it works perfectly normal...This one I feel has a technical problem that needs repair....Any suggestions? Thank you for any advice. I am a retired Electronic Design Engineer and my specialty was Video Design. Marve Rohfeld....marve.rohfeld@yahoo.com