I'm using a new iPhone 3G S and downloaded the Pandora app. I bought an extra apple dock so it can charge on my desktop and I've got a cable going from the audio out on the dock to the audio in in back of my MP so I can take advantage of the speakers I've got connected to the MP. The problem is that whenever a song is play I can't control the song volume through Pandora. the volume controls on the apple wireless keyboard don't work and it neither do the volume controls in iTunes. I can't seem to turn down the volume. How do I do this?