I am always on wifi and my airport works fine. when i tried to connect an ethernet cable to my macbook it wouldn't work. I made sure that it was set up for dhcp and it's able to pick up an ip address from the router but I can't get it working. Any ideas on what I could do? On a windows machine i'd uninstall/reinstall the nic from device manager, but i'm at a loss on what to do with a mac. I've tried multiple cables, so i know it's not the cable, i also know that it's not the router since i tried using multiple ports as well. It used to work, but it doesn't now. Ideas??