Hmmmm...I know Maximus growl when he is playing with his plush toys he throws them growls at them catches them shakes them around alot and growls...and if I try to grab it during that time he will also growl..BUT I still take it away and say no speak...then after he is quiet I give it back, my bf says I am taking away his instinctual growl and as long as he isn't trying to bite me I should leave him...he also doesn't growl when I touch his food or put my hand in his food bowl..lol..he actually moves aside and stand behind me till I am done doing what I had to do in his bowl (add something or take it away for whatever reason)..don't know if this really helps