i've got a 2011 camaro. When my S4 was on 4.1 or 4.2.2 i could pair phone audio and bluetooth music at the same time. now, it's a struggle to get the bluetooth music to play music if the phone audio is connected- essentially, when i connect both the phone and bluetooth music profiles, the phone is setting the phone audio as the sound output, and making it not go over the car audio. ... I also can duplicate this problem with some Motorola bluetooth headphones, though, so it's not the car in my case. it's a conflict between the two bluetooth profiles --- so now that I went and posted this, I think I have it fixed. I connected the phone to my headphones, both Media and call audio profiles. as suspected, i can't hear the audio playing in the google music app. I rebooted the phone, and now, after it restarted, and connected to both BT profiles again, it's working as it should. at least for now, so if you have trouble getting the audio output working, may connect everything like it is "supposed" to be and reboot the phone once.