Maryland Code, Transportation § 22-602

(a) A person may not drive on a highway in this State any motor vehicle or combination of vehicles of a type required to be registered under Title 13 of this article, in a manner that, at any time, at any speed, or under any condition of grade, load, acceleration, or deceleration, exceeds the maximum sound level limits established under § 22-601 of this subtitle for the operation of that type of motor vehicle or combination of vehicles.

(b) An owner or lessee of a motor vehicle may not permit to be driven on a highway in this State any motor vehicle or combination of vehicles of a type required to be registered under Title 13 of this article, in a manner that, at any time, at any speed, or under any condition of grade, load, acceleration, or deceleration, exceeds the maximum sound level limits established under § 22-601 of this subtitle for the operation of that type of motor vehicle or combination of vehicles.