SOLVED!! I had the exact same experiences as was mentioned in this post. Did the same things of toggling, etc.
Was actually in the middle of contacting Plantronics when I got the idea of doing a Hard-Reboot of the iphone 5. Press and hold the Power and Home button for 5 seconds or so until the phone instantly turns off. After waiting a minute I powered the iPhone5 back on, went to Bluetooth discovery, powered on my Voyager520 and chose the option to pair it - was prompted for the pairing code and Voila! It worked.
I did find that after about 30 seconds, it lost bluetooth connectivity but I merely tapped the Voyager once to re-establish the bluetooth connection and all was fine.
Re: Siri - Yes, it's anoying that Siri wants to take over. I found that if you wait a little longer - it evntually dials the number.
Re: Static I did some tests and the sound the caller receives is a high-pitched wine sound. Obviously there is some interference coming in as you cannot hear it on the Voyager BT. I haven't tried this yet but I wonder if there is interference from the LTE antenna or wifi & LTE together during a BT call.