QL, this is kind of what I suspect is going on with my Linksys BEFW11S4...it worked for about a week, then went out. Test site 192.168.1.1 shows all is OK, WLAN link and ACT lights come on, but the laptop doesn't pick up the hub/router signal 20 feet away.
An uninstall/reinstall and driver / firmware update check did nothing...the card in the laptop seems to work OK on other wireless networks (i.e. Wayport, Boingo, T-Mobile), but it's also been a hassle connecting at times, like it has a mind of its' own.
I think I'll take your advice and start over...I kind of thought this thing was a POS.