Abstract: A method and system for changing a digital signal processing (DSP) mode of an audio system in a motor vehicle having a roof movable between open and closed positions. The open/closed position of the roof is determined and the audio system is operated in a first DSP mode when the roof is in the closed position and operated in a second DSP mode when the roof in the open position. The first and second DSP modes have different processing characteristics adapted for the acoustics of the passenger cabin when the roof is closed or open. The open/closed roof position may be determined by a roof position sensor or by the actuation of a roof position switch operated by a vehicle occupant.