When Stomper learned Gregory House was going to be released from prison, he demanded that House give him his portable stereo. Stomper couldn't take it while House was there because House was protected by the New Confederates gang. To make it clear to House what would happen if he refused, he urinated on the floor House was cleaning up.
To get Stomper off his back, and to get back at Rollo for also trying to take advantage of his upcoming departure, House hid his stereo in Rollo's cell. When Stomper came looking for the stereo, House told him that he had put it in Stomper's cell, but then had seen Rollo stealing it. Stomper didn't believe House, but went to Rollo's cell and found the stereo. He and Rollo got into a fight and they were both sent to solitary confinement.