If he's not on the battlefield, you can typically find Knock Out out on patrol, where he can keep his mind off of things that upset him. Because a lot of things upset him. A lot. And when he gets upset, he gets violent. He's one angry little bot with a seemingly endless supply of bile, a fact that he's well aware of. He figures that that it's better to be out specifically looking for Decepticons so at least when he goes ballistic, he goes ballistic on them.