X31 believes its power is being disconnected, but it's not.

[rikkus]

When my X31 is on mains power, at random intervals the power beep sounds and the screen is dimmed or brightened. This can happen often, sometimes once or twice per second, sometimes only once every few minutes or hours.

I assumed there had been too much strain on the power socket, so I took the system to bits and saw that it looked fine, so I was a bit puzzled as to what was happening.

I then tried removing the battery and the system still runs while it 'thinks' it has no power. Strange, indeed.

Any ideas what could be causing this and how to stop it?