just wanted to add my related problem... I have a 2014 Honda Insight, does not have BlueTooth, but I connect my iPhone through USB... after updating to iOS8 it would connect to my car but i was not able to control the iPhone - would not start playing automatically and could nto skip tracks. I reset Network Settings which fixed the issue, until I rejoined my home WiFi Network.... then I reset Network Settings again, and joined my WiFi network, and now it has continued to work for the past week.
However, Last night I received a call while connected to my car, which i Answered, and then upon plugging back in, it stopped working again. Powering off my Iphone and starting it again fixed it this time, so all is well again for now...
i do keep bluetooth turned ON, but i do use it for anything or have any devices synced...
it seems to me this blutooth issue may be related to my USB issue