Only slewing east with android app? #lx200


I've got an LX200 alt/az onstep setup, but a few times now I've had it enter into a state where the android app (which is my main way of fine tuning the position) will only move it in one direction on the left/right axis - if I press east, it moves east. If I press west, it moves... East. North/south work as intended.

This happened again last night, and I plugged in the basic hand controller and it was able to move in all directions as expected.

Any ideas why this may be happening and any ways I could diagnose/fix it (or even a workaround)?