A speaker or microphone module includes an acoustic membrane and at least one pressure vent. The pressure vent equalizes barometric pressure on a first side of the acoustic membrane with barometric pressure on a second side of the acoustic membrane. Further, the pressure vent is located in an acoustic path of the speaker or microphone module. In this way, differences between barometric pressures on the different sides of the acoustic membrane may not hinder movement of the acoustic membrane. In one or more implementations, the pressure vent may be acoustically opaque. As the pressure vent is located in the acoustic path of the speaker or microphone module, being acoustically opaque may ensure that the pressure vent itself does not interfere with the operation of the speaker or microphone module.