A muffler (1) for an exhaust system of a vehicle driven by an internal combustion engine, includes a gas-tight housing (2), a partition wall (31) inside the housing, an inlet pipe (51), a first outlet pipe (61), a switchable second outlet pipe (7) and a resonator pipe (8). The a partition wall (31) divides the housing's interior into a first volume (41) and a second separate volume (42). The inlet pipe and the first outlet pipe (61) and the second outlet pipe and the resonator pipe are in fluid communication with the first volume. The resonator pipe provides fluid communication between the first volume and the second volume. The second outlet pipe passes through the second volume. The second outlet pipe is surrounded, in a circumferential direction, by the resonator pipe in a section in which the second outlet pipe penetrates the partition wall.