Symptom
No sound from a device
connected by the back-up
audio cable
Poor sound quality from a
device connected by audio cable
Battery won't charge
Noise cancelling function
doesn't work
ENGLISH 15
Solution
• Secure the ends of the back-up audio cable.
• Increase the volume on your headphones, your mobile device and music source.
• Connect another device (see page 11).
• Secure the ends of the back-up audio cable.
• Connect another device (see page 11).
• Secure the ends of the USB charging cable.
• Try another charging source.
• If your headphones have been exposed to high or low temperatures,
let the headphones return to room temperature and try charging again.
• Make sure that the noise canceling function is turned on.
• Are the ears all wrapped and re-equipped.Adjust the earpad position to fit your ears.If the
earmuffs are loose, re-set the ear.
• Eliminate low frequency noise? The noise canceling function is effective in low frequency
ranges such as airplanes, trains, offices, near air-conditioning, and is not as effective for
higher frequencies, such as human voices.