IPhone 2G WiFi not working, even after iTunes restore - How can I fix this?

Wi-Fi on my iPhone 2G is no longer working. Sometimes it will connect for a second and then disconnect, sometimes it cannot find any wireless at all. The device also freezes up when connecting/losing connection. All this still happens even when restored via iTunes and even after a DFU reset. This is NOT a router problem as it apples to ALL wireless connections on this iPhone, including public hot-spots etc. Any help would be appreciated but please note that I have already tried the obvious.