Sony WF-1000XM4 Manual page 87

Hint
The headset volume during a call and during music playback can be independently adjusted. Changing the call volume does not
change the volume of music playback and vice versa.
You can also enjoy hands-free calls even when you wear only one unit of the headset. If you wear the other unit while you are
talking with only one unit, you can talk with both units.
Note
Use a smartphone or mobile phone at least 50 cm (19.69 in.) away from the headset. Noise may result if the smartphone or
mobile phone is too close to the headset.
Your voice will be heard from the headset through the headset's microphones (Sidetone function). In this case, ambient sounds
or the sounds of the headset operation may be heard through the headset, but this is not a malfunction.
Even when the volume adjustment function has been assigned to the touch sensor, you cannot adjust the volume on the headset
during a call. Adjust the volume on the connected device. If you are unable to adjust the volume on the connected device, install
the "Sony | Headphones Connect" smartphone app and adjust the volume in the app.
Related Topic
Using only one unit of the headset
How to make a wireless connection to Bluetooth devices
Receiving a call
Functions for a phone call
5-027-983-11(1) Copyright 2021 Sony Corporation
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