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HD 4.50BTNC/HD 4.50R
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Troubleshooting
Troubleshooting
Problem
Possible cause
Possible solution
Page
Headphones
cannot be
switched on
Battery is empty
Charge the headphones
Battery is completely
exhausted/worn out
Visit an authorized
Sennheiser service center
for battery replacement
No audio signal Headphones are not
paired with your device
Check if the headphones
are paired. If necessary,
pair the headphones with
the device again
Volume too low
Increase the volume
Headphones are
switched off
Switch the headphones on
Headphones
cannot connect
Pairing does not work
Check if your smartphone
supports the HFP or HSP
Bluetooth
profile
Smartphone is
switched off
Switch your smartphone
on
Bluetooth
is
deactivated on your
smartphone
Activate
Bluetooth
on your
smartphone
Headphones
do not respond
to any button
press
Headphones are not
functioning properly
Restart the headphones by
switching them off and on
again
No audio signal Headphones are not
paired with your device
Check if the headphones
are paired. If necessary,
pair the headphones with
the device again
Volume too low
Increase the volume
Headphones are
switched off
Switch the headphones on
Headphones
do not
automatically
go to pairing
mode
Headphones must have
been paired previously
to some devices
Switch the headphones
off and press the power
button for 4 seconds
If you encounter a problem that is not listed in the table, or if the solutions
provided do not work, please contact an authorized Sennheiser service partner
for assistance.
To find a Sennheiser service partner in your country, visit www.sennheiser.com.