I have managed to pair a logitech bluetooth keyboard to my N810. It then shows up in the list of paired devices and I can use it just fine. But after I power off the N810 and turn it back on, even when the keyboard is in discoverable mode, I have to delete the device, and go through the pairing all over again to be able to connect and use the BT keyboard.

What is the trick to getting the pairing to persist and automatically reconnect after both the N810 and the keyboard have been turned off and then back on?