An actuator provides vibrational stimulation to a recipient of a bone conduction device. To ensure proper operation of the actuator, a known signal is delivered to a coil associated therewith. An output signal from the coil is analyzed for distortion, the presence of which indicates that the actuator is out of balance. If distortion is present, adjustments are made to the position of certain embodiments within the actuator to obtain a properly balanced device. Methods also include testing for distortion, after manufacture of the device.
