How do I get my DVD player to function properly?

I own a Philips DVP642 DVD player, and as of recently, whenever I try to use it, the disk tray opens and closes every few seconds after I turn it on. I only pressed the open/close button once upon turning it on tonight, and I lost count how many times the disk tray had been ejected, regardless of whether there was a disk in it or not. Nothing I press works. Sometimes, the message on the front of the unit will change to "Loading", "Play", or something else, but the unit will continue to open and close.

Is this something I can fix at home, or will I have to send this to get repaired?