A sensor assembly for mounting a microphone to an aperture of a vehicle trim panel. The microphone is in a housing with an opening permitting ambient sound to reach the microphone. A sound channel has a grid portion in the form of a first radially extending flange at a first end and an engagement portion in the form of a second radially extending flange at the other end which engages a T-slot recess on the underside of the housing. When the engagement portion engages with the T-slot recess and slides to a closed end of the recess, the sound passage is aligned with the microphone.