When we bought our A the gent showing us how things worked repeatedly stated "Level first, the slides have 2 motors, once you push the button to extend or retract you continue until its done, if you do not the motors may no longer be in sync with each other. Also its all in or all out so they stay in sync." So far we have had no issues as we continue to follow those instructions.
Though he knew nothing about batteries they both had the bulge from being frozen and needed to be replaced from sitting at the dealer through the winter.