Yes, the laser block travels on a rail and a bearing ball and as Graham already suggested, clearing this fault is often a matter of cleaning and lubricating of the laser carriage rail.
The old lubricant collects dust and dirt and seems to be especially fond of smoke particles. It hardens and starts to bind the carriage.
Clean gently and add a tiny amount of fresh silicone grease, You can play a 70min+ CD and jump to the last track to access the frontmost parts of the rail.
There could be electronic faults resulting in the same behaviour but the above mentioned is by far the most common cause.
Martin