I've had such a thing happen on my network when there where network problems.
It turned out that one Token Ring device (connected through a bridge to the Ethernet-network) was faulty and generating 'beacon errors'. In turn, this resulted in a high number of broadcasts on the Ethernet network. While this only caused some small problems on the Ethernet network, it made The Dude completely flip.
Perhaps you have got some device on your network that is causing 'broadcast storms', this seems to cause the Dude to flip-out.