Hiya Mark
Im always having trouble with the wireless on my super hub. Every now and then i have to restore factory defaults.
Try changing the wireless 802.11 mode to 145mbps, make sure the band is 2.4Ghz. Security mode should be WPA auto. Also remember any cordless house hold appliances will interfere with it so just change the wireless channel. I have mine on 11 as i have cordless house phone. I find with those setting the kids get wireless ok on their DSi's, the Wii connects and keeps the missus happy with her lappy.