Hello there. We have a 2008 Grand Touring with Bose audio and navigation and have lost Bluetooth capability. Pressing the phone button on the steering wheel gives no response. I'm curious as to what might be the best/cheapest option for remediation:

1) have head unit diagnosed/repaired by 3rd party car audio place
2) purchase used replacement head unit from EBay, etc.
3) have dealer sort it out (not likely viable - too costly)

Any thoughts?