You should be able to hear a beep when enabling the option in settings. But since (as has already been mentioned) the Bangle 2 doesn't have a speaker the vibration motor is used at high frequency instead. And with the vibration motor being rather weak to start with it'll be very quiet...
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
You should be able to hear a beep when enabling the option in settings. But since (as has already been mentioned) the Bangle 2 doesn't have a speaker the vibration motor is used at high frequency instead. And with the vibration motor being rather weak to start with it'll be very quiet...