Lenovo W520 User Manual page 12

disconnect the charging cable and
power on the headset for re-pairing. The
device should work again.
Problem: Unable to mute the device
using the headset.
Solution: Limited by the Bluetooth
agreement, some devices support the
mute operation on only one device. In
this case, switch the mute function from
the device (mobile phone or computer)
to the headset.
Notice
 Long-term exposure to high-volume
sounds might result in serious hearing
damage.
 For your safety, do not use the headset
under risky conditions, such as when
you are driving or riding.
 Ensure that you distinguish the left and
right ear buds when you use the