I recently finished my basement and put together a home entertainment system. I ran ethernet through the walls to a wall jack. I plugged my laptop into it and it tested good (internet worked and pinged my router 1ms time & 64 TTL.) I put an A/V rack in front of it and brought down my Netgear GS605 switch, XBox360, BD player that had all been on the network upstairs and added a new LAN capable receiver. None of those components will recognize the network. Light doesn't light on the switch(neither amber nor green,) Xbox doesn't recognize a cable is even plugged in. I unplug the switch and using the same cables my laptop picks it up just fine. I bypassed the switch and went strait to the other A/V gear and none of them recognize the network.
By the way, the switch is auto detect between patch/crosssover. The IP settings are all the same from when the gear was connected upstairs.