If you get thrust movement with the throttle at 0%, you may have a faulty unit.
What I've seen happen is the little detent plate in the throttle rise up out of it's socket and lose, or bend, a spring so that it can't sit back in and be a detent - so the rubber teeth on the bottom of the throttle can never let the throttle reach exactly all the way to the rest point. That will give a constant throttle output.
It's a five minute fix to pull the thing out like a bad tooth, but if your unit is still under warranty - send it back for a new one!