I have a Neo ProLink (essentially the same as the USA Spec) car adapter that I've used for the last few years and I love it. I currently have my iPhone 4 on it. I'm considering upgrading to the iPhone 5, but I'm getting mixed messages about what the Dock to Lightning connector lets you do. Has anyone with this type of car adapter tried slapping the Lightning adapter on there and used an iPhone 5? I'm hoping the charging and radio controls continue to work. I wish they would just produce the cable needed, but they don't (yet?) so I have to go the adapter route.

 

Always consider the source. Per Apple the only things not supported by the adapter are iPod out and video out. A lot of people don't seem to have a clue what iPod out means. I've had no problems with my wife's iPhone 5 and the USA Spec interface in her car.

The Lightning connector's still new and not every manufacturer is willing to jump through the hoops required to license and/or manufacture accessories with the connector. Have you contacted the manufacturer of your interface?

 

This thread may be of some use.

Prepare to bend over for Apple (as usual)...