MULTIPLE IPs, same NIC??

I have a new Roamio device. It is NOT connected in ANY WAY to Wireless. It has ONE NIC card in the back. I have it set for a STATIC IP of 192.168.0.91, yet, on my router, under ATTACHED DEVICES, the TIVO######### device name shows up TWICE... two different MAC addresses, but they are extremely similar (last octet only is different) so I know it's the same device... but it always has TWO IPs on my local network. Any idea?