My iPhone used to work beautifully with the USB connection, I could listen to music, podcasts, even get gps info. Then, all the sudden it will not work. Anyone have any idea what is going on here? I just did the update on the iPhone to 9.2.1, so I'm not sure if that is the root cause to the problem or not. Thanks for your help.

 

it's not uncommon for phone OS upgrades to cause compatibility problems. sometimes it's a setting change or default change that you can fix yourself. other times it's total compatibility/feature loss that is only corrected with another OS update (after the bugs are reported).

in your phone settings, check for audio output via USB being supported. also check iPhone forums for the same.

 

also check the cable. I have seen cables go bad over time. don't know why, just what I have seen