Probably the laser is sticking...open up the unit you'll see the laser pick-up assembly with the lens. Caution: don't look directly down into the lens when it's on.
It slides back and forth on 2 rails...so clean the rails with a Q-tip. If that doesn't work maybe the sled motor is bad, sometimes they will work but after awhile they get stuck in a certain position.
You'll see a motor next to the laser pick-up that moves the lens back and forth. Spray a little DW-40 down inside the motor. Of if you can find a junk DVD player you can pull one of the motors out of it and use it as a replacement.
bob, November 2010
