Sounds like educated rabbits, that know the lamp spells danger, have you been lamping them too often, or have you lampers on your ground?
if the hedge has burys, maybe best ferreting it.
its my pals land this is the 2nd time i have been on with the lamp with him and i go past it to get to mine and there is all ways lampers on its not kept so its free rane it was hard work getting just the one last night