The transmitter features an automatic on/off function. When the transmitter is turned on, its green LED lights up. Make sure to turn off the headphones after each use to avoid discharging the batteries. Reception Adjust the receiver channel with the TUNE control on the headphones. If reception is subject to interference, change the transmission channel. To do so, set the switch at the bottom of the transmitter to another position and re-adjust the receiver channel. Some electronic devices (e.g.