I upgraded to iOS 4 on my iPhone 4 last night and everything went well. This morning, I plugged my iPhone into my car stereo using the USB port (something I do on a daily basis) to listen to music on the way to work. In about 5 seconds, I noticed that the music kept cutting out. I unplugged the USB and plugged it back in thinking maybe there was a connection issue. I got the same result - the music kept cutting out. When I listen to the iPod through the speakers on the iPhone, it was working fine. Has anyone else run into this issue?