Iíve had a Challenger for almost 10 years. I recently changed the blades and properly cleaned it for the first time, oops! I noticed the housing for the bottom burr lifts up and down, the housing also doubles as the distributed for Pushing the grind out (I have the doserless model). I can hear it bobbling when grinding which would likely mean grind is getting caught underneath it and compacted, and must also mean inconsistent grind. I hadnít noticed it before but it was probably something thatís always happened. My question is, is this normal functioning? Or do I need to pull it apart and deal with it?