I was unable to connect to my Delta 2 until I power cycled the whole unit. The radios appear to be powered off after an unknown amount of time, possibly only if they are not configured. To power cycle the unit, you have to turn off all power outputs, disconnect all power inputs, then hold the power button for three seconds. Bluetooth paired with the app immediately upon turning the unit back on. I did not have to turn on Bluetooth using WiFi, as was suggested somewhere else. It is worth connecting and checking out the app since there are some very useful settings in there.