CG3000D

I just got a netgear CG3000D modem/router from Cox. It has a USB port, which is, in theory, suppose to work with a external drive or printer. Neither works. Nothing is mentioned about the USB port in the Cox supplied documentation. In an internet instruction (not from Cox, from Netgear Australia), the CG3000D instructions mention that the USB port may need updated firmware to work. My conclusion is that Cox provides a version of the CG3000D that does not allow enabling the USB port. Anyone have experience with using an active USB port on the CG3000D from Cox? I assume the USB port from Cox is useless.