invalid source port message?

[don fisher]

I have a CISCO E4200 router, recently installed. I am receiving the 
following message in /var/log/messages

avahi-daemon[1029]: Received response from host 192.168.7.1 with invalid 
source port 32783 on interface 'eth0.0'

192.168.7.1 is the address for the E4200 router. Where does this address 
come from and how do I fix it?

Thanks,
Don