FD-626 - Filament Driver

When I received my very first 3D printer kit, which was a RepRapPro Huxley and became Huxy 1 (now you may got a glue of where the name of Huxy is coming from), I was very happy and amazed of various things in the pack. The most exciting was the "extruder driver" - well, I prefer to call it "filament driver", cause that it is :) A very nice piece of engineering, with tiny 623 bearings, though very compact.
After assembling everything and get the first prints the problem appeared. The driver was