Hey boss,
I've never heard of this issue with the S11. Does it happen with any song you might be playing and moving around? That's really weird. I would try updating the firmware on the S11, but before that resetting it back to factory defaults from the screen on it. See if the factory reset fixes it and if not, then try the firmware update. Even if it's already on the most recent firmware. Make sure to let the firmware update complete and don't turn off the S11 to avoid bricking it. Please report back what happens. L8r!