Thank you so much for your inquiry. For total convenience, these headphones support Multipoint feature which allows you to connect 2 Bluetooth devices (smartphone, tablet, laptop, etc.) to the headphones simultaneously. So when a call comes in, your headphones know which device is ringing and connects to the right one automatically. You’ll also be able to quickly switch your headphones to either of the two devices at the touch of a button.
• When Bluetooth connections are established between 2 devices and the headset, another paired device can be connected via Bluetooth connection.
• If you try to make a Bluetooth connection with the headset by operating the third device, the Bluetooth connection with the last device that played music will be maintained, and the Bluetooth connection with the other device will be disconnected. Then a Bluetooth connection between the third device and the headset is established.
For more on "Connecting the headset to 2 devices simultaneously (multipoint connection)", please check our help guide link here: https://helpguide.sony.net/mdr/wh1000xm5/v1/en/contents/TP1000541784.html