I've had this issue for a while. Cleaned the ice maker a few times, tried to isolate the source but never could. After cleaning the ice bin each time it made ice there would be an "ice dam" forming underneath. After about a week it would build to the bottom of the ice maker and I'd have to pull the bin, dump the ice dam (now about half the capacity of the bin) and start over. After looking at other posts with the same problem it appeared replacing the ice maker assembly was the cure. So I did it, a few days in and no ice formation! So I still am not sure where the actual leak was coming from but its resolved now!