Could it be that you can dock the ipod but can only connect an mp3 with a cable. It would not be very smart for Honda to support only ipod.
I just bought one on Christmas Eve and it seems as though only an Apple Ipod can be used to plug in and play through the stereo. I plugged my MP3 player in, but no sound came out. The Honda's owner manual mentions Apple Ipods with iTunes, but Honda's website mentions MP3 players Help.

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