This problem can also be caused by a hardware initialization error. I\'ve encountered the exact same thing. This is what worked for me, found on these forums prior to loss:
Turn off gbox, turn off TV, turn on Gbox wait a second, turn on tv.
For some reason this prevents conflict with the wifi hardware initialization at boot. In fact, I\'ve practically started making it a point to turn the gbox on before the tv, or just leave it on all the time.