Samsung SM-G970F/DS User Manual page 71

Apps and features
Using earphones or a Bluetooth headset
Connect earphones or a Bluetooth headset to the device when your voice is not heard clearly
via the built-in microphone due to noisy environments. Press and hold the Call button on
earphones or a Bluetooth headset to start a conversation with Bixby.
This feature may not be available or its method of use may vary depending on the
earphones and Bluetooth headset.
Call button
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