Hello ttsugar, I've read your post about the pairing issue, I've got the same too.
I've experienced this troubles with two new phones, both with MTK6592 - octacore -, when tried to connect to my car audio device: the phones are the Cubot X6, and the Star N9800; my car DVD combo player is from EONON brand.
With my old phones all worked at the top, as regards all the bluetooth functions. Still with my iNew V3 the pairing works like a delight, and all the bluetooth functions were good at all.
I surfed the internet to find a solution, tried some patches, but nothing to do with the new octacore, the song remains the same : "..,invalid passkey..." . no way to introduce the pairing code.
I don't think that the problem is the 4.2.2 android version, becouse my iNew V3 has got this version too, and works perfectly...
I really think that the problem stands in the different hardware of the bluetooth chipset included in the new MTK6592 ( they speak about 4.0 ), so the protocol doesn't communicate well with the old devices.
Hope to find a solution asap, I need the same too !