A semiconductor device includes a first substrate and a second substrate being bonded to each other, a posterior interconnect layer interposed between the first and second substrates, a weld pad disposed in the posterior interconnect layer, and a first annular opening disposed in the first substrate. A process has been developed for modifying the processing parameters to shift the non-zero offset voltage closer to zero. In one implementation, the control signal indicates that a delay adjustment should be made only if both PDs agree on that adjustment. The controller controls various kinds of operations of the speakers and the amplifiers by allowing a user to control the matrix circuit by a multicast method so as to select amplifiers or a combination thereof to be used for broadcasting using a keyboard or a mouse. In one embodiment of the invention, the device includes a base lip that applies a lateral force to the skin when the base lip is pressed against the skin.