Ok, I have my rovio setup to DHCP an IP address from my linux server, it's setup statically (on the server) so that it always gets the same IP.
My linux server is also a masquarading gateway with the apropreate ports forwarded so that I can connect to the rovio externally. This works as it should, and I can control the robot remotely.
The wifi is setup with WPA2 encryption.
However lately I have been having the following problem.