Sennheiser BTD 500 USB Notice D'emploi page 6

Connecting the BTD 500 USB
1 Activate pairing mode on your Bluetooth headset.
2 Plug the adapter into the USB port.
1
When you connect the adapter for the first time, it
switches to pairing mode (3) and automatically connects
to your Bluetooth headset (4).
3
If the adapter cannot detect a Bluetooth headset within
5 minutes, the LED goes off.
Restart the procedure.
2
ON
4
5