If I plug an ethernet cable it works fine. I use a WEP password on my two wire 2701HG-B. When it fails I have to turn off wifi for about 15 seconds then turn it back on. Or, I have to tell it to join other networks thn put in my network and pass. I do this at least five times after opening Safari and trying to browse.
I have checked keychain repeatedly and all looks fine but this still happens.