[. . . ] Place the transmitter near to your hi-fi system, your TV or another audio source. Connect the power supply to the power supply port of the transmitter and then insert the plug into a power outlet. Set the volume of your audio source to 1/4 to 1/3 of the maximum volume and connect the other end of the cable to your transmitter. Connect the digital output (Toslink) of your DVD player or any other digital audio source to the digital input of the transmitter. [. . . ] Use a suitable Toslink cable for this purpose (not part of supplied kit). The operation indicator light of the transmitter glows blue when music is received. Please read these operating instructions carefully and keep them in a safe place. Then also press within 10 seconds on the pairing button on the headphone. Press the A/D button of the cordless headphones to switch between the two audio sources. Caution: With some DVD players or other digital audio sources, the Toslink output has to be activated. Remember to also switch to the correct input on the cordless headphones (A/D). Thereafter, press the Pairing button of the cordless headphones for 10 seconds and thus confirm your selection. If you wish to operate several sets in parallel, repeat steps 1-5 for the next set. "Total Privacy" ­ Anti-eavesdropping security Thanks to the latest wireless technology, the possibility of listening in by third parties is eliminated and you can fully enjoy your private sphere. Charging of the rechargeable batteries starts automatically and the charging indicator light of the charging tray switches to red. If the charging indicator light does not become red, move the headphone a little back and forth in the charging tray till the charging contacts engage correctly and the charging indicator light glows red. Caution: Before using the batteries the first time, charge them continuously for 8 hours to achieve full capacity. the cordless headphone set has a charge-protecting battery charging function for longer running time of the batteries. After about 8 hours, the discharged batteries get completely charged again and the charging indicator light goes off. You can now enjoy your music for about 11 hours at average loudness levels. Using different batteries The RF headphone can also be used with other chargeable standard AAA micro batteries or non-chargeable 1. Standard chargeable AAA micro batteries cannot, however, be charged via the devices. Disposing of the batteries and rechargeable batteries Consider the environment when disposing of the batteries or rechargeable batteries, which must not be thrown away with domestic rubbish. Do not use old and new batteries or different battery types simultaneously. [. . . ] Do not use old and new batteries or different battery types simultaneously. Remove batteries from the device if it is not to be used for a long time. Problem No transmission / no sound Possible cause Devices are outside range Batteries are empty Connection cut off There is no signal at the input The transmitter and the cordless headphones are not coupled Incoming signal not loud enough The digital audio source (DVD player etc. ) is not correctly set Batteries are almost empty Devices are on outer margin of range Position of transmitter A beep resounds in the earphone No charging Batteries are almost empty Rechargeable batteries are not charged Check whether or not all plugs are correctly plugged in. [. . . ]