sony je series.Stops between tracks?

I have a couple of sony je 440 series (hi-fi seperates- not walkman types)and both have developed the same problem. As the current track comes to an end the 'smart space' lights up and the disc stops playing instead of going on to the next track automatically.This means I cannot play a recorded album all the way through, I have to press 'play' to go to the next track. Any ideas anyone? The same albums play quite normally on my walkman player so it is not the disc itself at fault.