These headphones have two volume settings—HI and LO. These settings control volume levels for audio only and do not impact the noise reduction technology.
For noise reduction only, turn the unit on HI or LO and do not plug the headset into any audio source.
For audio listening, use the LO setting and then adjust the volume on the audio source. For more volume, try the HI setting. First turn down the volume on the audio source, then switch to the HI setting. Finally, readjust the volume on the audio source.
You can use your headphones with a variety of audio sources, such as airline entertainment systems, CD/DVD/MP3 players, personal or laptop computers, and home stereos.