NSM City II ES2 Carriage travel issue...

I have one of the Ortofon ES2 machines and after finishing last record selection play, the carriage drops the record back into the rack, returns to the rest position at the right side of the rack and then does one of two funky things:

1.)

1.) After 20-30 seconds resting, it will mysteriously begin to travel toward the left end of the rack, pausing every couple of inches. After getting to the far left end, the carriage reverses, and begins to travel back to the right, then reverses again and again...never stopping and parking at the right as it is supposed to.

2.) Carriage will move all the way to the left, stops moving but the drive motor keeps trying, making a "click, click, click" sound.

This scenario makes it so that the machine cannot be left "on" when not playing as the carriage motor never gets a rest. Any ideas on what the heck would make this thing not stop moving? ANY input/suggestions are greatly appreciated!

Thank you.
-Joe

Wild guess as I'm not familiar with NSM at all. If this unit uses "electric eyes" to tell where the carriage is and what position it's in and where home position is, one or more may have failed or are dirty and need to be cleaned. Rowe uses a system like this on their later boxes. It sounds like the system doesn't know where "home" position is.