Off one's box

"Say, if you call that acting well, you're off your box."

"The 44-year-old has admitted to cleaning up his act of late, kicking well-publicised drug addictions and now leading a healthier lifestyle with regular exercise and a passion for fruit smoothies. He told the M.E.N. last week: "Innit just natural that when you're a kid you're off your box and when you're a grown up, you're not? It seems totally normal to me, that.""