When I switch between "Track" mode and "Pan" mode or "Edit Plugin" mode, the firstmost fader fails to set/reset to the correct position and usually flinches slightly and moves back to the previous mode's first fader value/position, sometimes also setting the value (incorrectly) in the DAW I am using. This happens more than 90% of the time and is very frustrating as I have to pause and reset the value.
Note that this doesn't happen when changing banks (that I've noticed), only when changing modes, and only on the first/left most fader.
EDIT: In MCU mode, with Ableton, MacOS 10.12, v1.01 of the firmware updated via UC.