Whats your ISP service? DSL or Cable? Whats your modem of ISP modem? Does it have a built in router or is it stand alone? Some with built in routers can be problematic with external routers. If it's got a built in router, can it be bridged? If not, does it have a DMZ?
I would try v2.03 FW and see if it does the same thing and set up a syslog server. There are free syslog server program to capture the data. I don't think this is a bug since others don't seem to see this issue including mine.