Most of today's playout devices (Set-Top-Box, DVD, Blu-ray, Gaming Console, act.) are controlled by using an infra-red (IR) signal. On one side, your remote control is transmitting an IR signal code once you press a key, and on the other side, your playout device has an IR Receiver that picks up this signal, analyze it's code and than the relevant action is performed.One of the biggest disadvantage of using IR as a control method is the fact the both, remote and playout device, needs to 'see' each other.Your screen has an IR receiver built-in (obviously for controlling all of the screen's features). The IR Out port of the screen is enabling the received IR code to 'pass-through' (re-transmitted) through those ports. This enables you to install your playout devices behind the mirror/glass or even in a remote location and still to be able to control them using an IR remote control.In most cases you'll use an IR Emitter connected to the IR Out2 (LED) on one side and on the other side you place the IR Emitter (LED) just on in front of you playout device IR receiver. The IR Out2 was designed for 5VDC IR Emitters using a 2.5mm MONO mini-jack plug. Pinout details are: Tip - Signal, Sleeve - GND. In some cases your playout device will have an extra port for 'wired' IR control signals. In this case please use the IR Out1 (Cable) using a 3.5mm STEREO mini-jack plug. Pinout details are: Tip - Not Used, Ring - Signal and Sleeve - GND