On the backside of your Bridge just above the USB-C power connection, there is a little power button that can also be used to mute all.
Turn on/off your Bridge
To turn on your Bridge - hold it until the LEDs turn on.
To turn off your Bridge - hold it until the LEDs turn off.
When you're logged in to your account the power button can also be used to mute all. Meaning no incoming signal will be received and no outgoing signal will be sent.
To mute all - click the power button once.
Unmute all - click the power button once or click the all muted button in Elk LIVE.