Hi /u/hale317. Don't know if this will solve your problem, but I bought an S4 last year and bought this from Amazon, https://www.amazon.com/gp/product/B017RVHSSQ/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 on the advice of another redditor and that solved my issue. Good luck.
Since you have a factory iPod dock you need this which tricks the car into thinking there is an iPod there. Just note that you have to have at least one song download to your phone. If you have swc they will not work unless you play downloaded music and won’t work on streaming services.
U don’t need a new head unit. I purchased this for my previous Audi with the same problem.
CoolStream Bluetooth Adapter for Audi and Volkswagen iPod iPhone Ami Cable CarPro https://www.amazon.com/dp/B017RVHSSQ/ref=cm_sw_r_cp_api_glt_fabc_XZ2SE163AZ7K46WEWN9P
It gives Bluetooth to the car and it just plugs into the mmi cable in ur glovebox
This might be a solution if you're just looking for bluetooth audio. It goes from usb (probably have to get the old thunderbolt to usb a) and plug it into the usb in the center console. Connect your phone via bluetooth to it.
I'm fairly certain audio streaming was not yet supported on the 2012 models. You'll need something like this to connect to the iPod adapter (for the AMI unit) in your glove box. If you don't have the one that came with the car, they're something like $20 online.
What year is your Audi?
Bluetooth Adapter for Audi and Volkswagen iPod iPhone AMI Cable – CoolStream CarPro https://www.amazon.com/dp/B017RVHSSQ/ref=cm_sw_r_cp_api_qiLuzbEKZDJ2W
This would take care of the not having audio Bluetooth available, I had one on my 2011 A4. Never failed.
Cool Stream Car Pro is what I use. I like how it automatically picks up when I turn on the car. Quality is good. Switching through songs I can go previous and next. But, I don't see any track or artists names. https://www.amazon.com/dp/B017RVHSSQ/ref=cm_sw_r_cp_apa_iY9HybD4BDRTA
It doesn't. You can use the AMI cable to connect an iPhone in the glove box. You might need an adapter for the lightning cable. I got one of these for bluetooth streaming.
https://www.amazon.com/gp/product/B017RVHSSQ/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
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This looks like it might work too. You will have to check the charts for your car though.
I ambsire there are others but this is what I got
Your car should have an AMI port and an AMI cable. Look it up. You may need to buy the cable if it's missing. Then you can plug in an iPhone and keep it in the glove box which is where the AMI port most likely is. Or you can buy a Bluetooth adapter so you can stream from any Bluetooth device.
I use this one. No issues so far. It was easy to setup. https://smile.amazon.com/gp/product/B017RVHSSQ/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1