I just installed a z150bh head unit in my xterra
I have a stock Nexus 4, not rooted.
In order to get it hooked up I switched out the MHL adapter for a slimport adapter that seems to work for most people.
Pandora, when operated from the avic screen rather than just a direct bluetooth audio, has issues staying connected. I will hear music from the car speakers for a few seconds, then from my phone for a few seconds.
I checked the bluetooth menu on my Nexus 4 and noticed the connection status switching back and forth from a normal connection to a connection "without media" every few