Techniques for automatically muting or unmuting an acoustic transducer include receiving a signal representing an output by a voice accelerometer of a device, determining whether the signal is indicative of a presence or absence of voice activity by a user of the device, and generating a control signal that causes an acoustic transducer to be muted responsive to determining that the signal is indicative of an absence of voice activity by the user, or that causes the acoustic transducer to be unmuted response to determining that the signal is indicative of a presence of voice activity by the user.