iPod won't work

Has anyone had problems with connecting an iPod to the bz4x? I have an older iPod nano that used to work just fine in my Prius Prime, and an even older iPod that used to work in our RAV4. Neither one will work in the bz4x. It won't even show up on the sources. I'm plugging them into the USB connector in the phone charging area. Am I doing something wrong or are they just not compatible with the car? Thanks for any insight.