If I test my internet speed from the LAN line from my modem I get the full 400mbps download I should be getting. If I run through the router at all (LAN or wireless) I get 140mbps down. Why is this an

My configuration is Cable modem -> switch -> Router -> Lan. When I monitor the traffic by mirroring the modem <-> router traffic I notice that the router is publishing my LAN network map via in-addr M