Using OverDrive Media from my library I can't transfer audiobooks to my ipod classic

Can anyone tell me how to configure my ipod Classic so I can transfer audiobooks from the library using OverDrive Media. These particular books are labeled "ipod compatible" but when I try to transfer, after downloading to my computer, I get an error message saying they can't be transferred to my ipod. I selected the option on my ipod to manually manage something which I know requires that I eject my ipod before disconnecting it from the computer. Any other help?