Google Assistant and Siri are activated by rapidly double-pressing the center button
I have a btc480 and double tapping the centre button calls the last number dialled! Is there something wrong with the device or the phone?
Let’s try triple tapping the center button to see if that triggers voice commands. If that doesn’t work, you can factory reset the BTC480:
Hold down both the skip-forward >> and skip-backward << buttons at the same time. The blue LED will blink purple and then go back to blue. The BTC480 will have been reset.
Delete the BTC480 from your device and then pair it again. Try triple-tapping the center button to see if that activate voice commands.