How can I fix my Sanyo Stereo, Model DCS-C60?

My Stereo will not stop changing cd trays when i want to play a cd. As well the Cd trays don't eject according to the tray i've indicated to eject. For example: if i want to eject the disc in tray 1, the stereo will eject the disc in either tray 2 or 3. If I wanted the disc in tray 2, I get the disc in either tray 1 or 3...you get the picture. All i need to know is how to get the trays to stop changing and how to get them to eject properly.