On your computer, click Settings > Devices ... to multiple devices via Bluetooth Multipoint Most modern wireless Sony ...

3] Connect your Bluetooth headphones to another computer (if available) You can also do this. If another computer is available, connect your headphones to it and check if you experience bad sound ...

Don't forget to open the case before you hold the button so that the earbuds can 'see' the device they are trying to connect to, or they won't enter pairing mode. The LED will flash to show you are in ...