We’ve noticed that the MB660 doesn’t like to go into pairing mode when you’re talking on it. So, you’ll try this:
1) If the you're on a cell phone, turn off Bluetooth on the phone. This will kick the call back into the regular cell phone. If you're on a computer, first make sure you're not speaking through the computer (like Skype), then once you’re on a different phone, unplug the USB Bluetooth dongle.
2) Once the way the headset was originally paired is blocked, put the 2nd device into pairing mode. Then, turn the headset off (turn the headphones so they’re flat) and then back on (turn them back out) so that the headsets says “Power On.” It should then say “Pairing.”
3) The headset should pair to the 2nd device like magic! It will say “Pairing Successful” when it’s done.
4) Then, you can either turn the Bluetooth back on on the cell phone, or plug the USB dongle back in. The headset will then pair to the original device again because it should remember it.
5) Then SHAZAM! You’re now paired to both devices!