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HD 4.50BTNC/HD 4.50R
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Using the headphones
Using NoiseGard
The HD 4.50BTNC/HD 4.50R Wireless headphones provides excellent attenuation
of ambient noise using the
NoiseGard
Active Noise Cancellation technology.
You can activate or deactivate
NoiseGard
if your headphones are connected to
the smartphone using
Bluetooth
or the audio cable.
Activating/deactivating NoiseGard when connected via Bluetooth
X
Simultaneously press and hold the Volume
+/-
buttons.
The LED flashes purple 3 times.
NoiseGard
toggles between on and off.
Activating/deactivating NoiseGard when the audio cable is used
X
Press the power button.
NoiseGard
toggles between on and off. The LED lights up blue to indicate that
NoiseGard
is active.