Can you solve these intermittent audio problems with Ford Sync and iPhone?
Solution 1:
I don't have an answer, but I have the identical problem with an iPhone 3G. The sync system will recognize USB for about a month and then start failing until it flat out won't recognize anything device that is inserted into the USB port. I've had the guys at the dealership look at it 3 times and each time they get it to start working again by upgrading the sync software or it just happens to start working.
Have you found a solution beyond using Bluetooth? I can't even charge my phone anymore through the port.
Solution 2:
[Ford Sync Gen1, V3.1 (the latest for my 2010 Ford Contour). iPhone 4, iOS 5.0]
Playing music via BlueTooth: "volume", "next track" and "previous track" steering wheel controls work, but does not show track info on the dashboard.
Playing music via USB: does show track info on the dashboard, and (new with iOS5) "volume", "next track" and "previous track" steering wheel controls work.
*problem. To get USB sound I start the music on the iPhone, then plug in the USB cable, then (by voice) switch to USB. Switching directly from Bluetooth to USB seems to be working, but there is no sound. If I unplug USB, plug USB, switch (by voice) to USB, then I do get sound. At least I don't have to wait several hours like you!
Solution 3:
The problem is a faulty Apple design. They automatically route audio to the last connected destination. What you are describing is the Bluetooth connecting after the USB connection and even though in the vehicle you have USB selected the phone is routing audio to Bluetooth. If you disconnect the bluetooth or turn it off on the phone then the USB will always work.