Are you seeing your micro adjust move towards coarse when grinding?
If you notice your micro adjustment ring moving toward the coarse direction you can correct this by simply tightening the three screws on the bottom of the adjusting ring. To do this, remove the adjusting ring and burr and turn it over to see the screws, tighten the screws up a little (maybe a 1/16 of a turn) and re-install the adjustment ring/burr and you should be fine. Do not over tighten the screws or you risk stripping the threads.
If the issue persists it may be because there is insufficient friction between the micro adjust collar and adjustment assembly. This can be solved by inserting some felt shims. See this guide for instructions. The felt may be purchased at your local hardware store and cut to size or you can email us (Support@Baratza.com) with your shipping address and we will send them to you.