I'm having a problem with my 770 not turning on. I think the power button is broken, as pressing (and holding) it when the thing is on no longer brings up the 'power off' menu either. Pressing the power button to turn on - nothing happens, no white screen, nothing. Anyone else? I think it may need returning; I'm going on holiday at the weekend so I reckon I'll just try to avoid switching off and return it when I get back ;-)