Hmm...that doesn't seem to be operating properly. It could be for some reason your iPod that's not functioning properly. When I designed the interface, I specified that it would operate like you are saying, if you are in the middle of the song, press the back button and it starts the current song over. If you are towards the beginning of the song, it will go to the previous song, but it shouldn't always do that. Are you able to test it with a USB drive to see if it functions the same way? Unfortunately I don't have quick access to a Camaro to test this out myself, but if I get a chance soon I'll see what happens when I press the previous button.
I work for GM and I designed the interface for the Camaro USB and Bluetooth audio streaming interface. Feel free to ask me any questions you have about how the USB or Bluetooth works!
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