An indicator for use with a microphone of a vehicular audio system, such as a cellular telephone, emergency communication device, or other audio device, provides a user of the audio system with a status signal relating to a reception quality of a vocal signal from the user. The microphone may be mounted within an accessory module, which may be mounted to an interior surface of a vehicle windshield. The accessory module houses a microphone and may be positioned adjacent to a headliner of the vehicle generally above an interior rearview mirror which is supported therebelow. The accessory module provides a fixed orientation of the microphone and is easily installed to the vehicle as it is manufactured or as an aftermarket device. The accessory module may further include a wire cover, which extends to a mounting for the mirror in order to substantially encase a mirror wire harness, thereby retaining the mirror harness and providing a finished appearance to the mirror and accessory module. The indicator may be mounted at the accessory module or elsewhere at the mirror assembly.