Mine is fixed and works great...
Got my 25DS back from the shop. Installed new gearbox. They did find that the assembly was installed with a slight tilt, as Stephan had suggested. Reinstalled it level and works fine. WE suspect that with the unit tilted the chains might have been rubbing on the side of the gears, overloading the gearbox.
Seems like a lot of problems with bedroom slides, but haven't heard about front slides on FR3's. I can't even find where the motor and gearbox access is for the front slider.
2014 FR3 25DS (Bought 2-22-2014)