Sennheiser MX W1 Instruction Manual page 22

Hum
Earphones
cannot be
switched on
Interference due to
charging via a USB
socket of a PC while
listening to music from
the same PC
Rechargeable batteries
have just been replaced
Charge from the
power supply unit or
choose a different
audio source
Resetting the transmitter to the factory settings
J
In case of system malfunction:
.
~
Use a pointed tool to press the reset button
for 1 second.
~~~~
The transmitter is reset to the factory
settings and then restarted.
If a problem occurs that is not listed in the above table or if the
problem cannot be solved with the proposed solutions, please
contact your local Sennheiser agent for assistance.
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