iPhone 4S music controls when plugged into car

[Dshan18]

So I have the 4s and I did the iOS6 update and the music app updated with that. I have a USB connection to my car radio that I use all the time and before I updated iOS I could change songs using raio controls or double clicking the home button and the previous, pause, and next button come up. Since I have updated it I have to unlock my phone and change the songs from within the music app itself. I can no longer do it from the lock screen or from the radio itself. Any ideas on why that is happening? I tried messing with the settings on the radio and nothing works so I think it has to do with the phone some how. Help! Thanks in advanced!