The USB connection is not yet fully I-Pod compatible so only plays MP3's and not the I-Pod's native AAC format, I corrected this in mine by having iTunes convert all tracks to MP3. Unfortunately you do loose some space doing this but not a huge amount.
Kia say full I-Pod compatability is coming, with some luck they will offer an upgarde as I suspect it will just be software based. (please KIA?
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