The B1 will automatically go into sleep mode and mutes the output after about 10 minutes. B1's sleep mode keeps important parts on so you can easily pair and connect devices to it; the light on the front will actually turn off when in sleep mode.  When in sleep mode, you shouldn't have to press any buttons on the B1 to reestablish the connection between it and the device as this is controlled by the bluetooth settings of whatever device you are using. 

To power down your B1 completely, you can either remove the external USB AC adapter from the power outlet or unplug the USB cable from the back of your B1.