In visit 2 of Building B, just after unlocking the gate with a code(the number is 1845 if you don't want to bother solving the puzzle) you'll come across a man staring at a wall talking about music. There's a red radio on the table to your right, take out your gun and shoot it. The man will ask where the music is, then get on the floor and curl up into a ball and then the achievement will unlock. All he wanted was to have some music to listen to while he's trapped in a run down asylum with some device attached to his head and no hope of getting out, but I guess getting your achievement was more important than letting him have a slight bit of happiness in an otherwise miserable life. You monster.