Just a FYI, the iPhone 4S and the manufacture installed iPod hook up in the MINI R56 work just great. I was surprised that it charges the phone with no problems too - I have had issues with previous models. It could be me but the sounds seems better too.

Good times in the MINI....

 

It's probably just you, I don't think the audio out changed from the 3G to the 3GS to the 4 to the 4S. And the only change from 2G to 3G was the headphone jack became unrecessed.