The D-RC4ST is a wall-box mounted remote module designed to directly control an RDL ST-SX4 Audio Switcher Module. The ST-SX4 provides solid-state switching of one of four unbalanced audio inputs to a single unbalanced audio output. The D-RC4ST connects directly to the POWER and CTRL terminals of the ST-SX4 using either a 3-conductor cable or a single shielded pair.The front panel of the D-RC4ST features four pushbuttons with four associated LEDs. Upon initial application of power, source 1 is selected. Touching any of the other three buttons de-selects source 1 and immediately selects the source corresponding to the button pushed. An LED, adjacent to each button shows which source is selected. For stereo installations, the SLAVE output from the ST-SX4 is used to drive the CTRL input of an additional ST-SX4.