Originally Posted by Groen
If that doesn't work, I am out of ideas.
You could try holding it for over a minute next..
Something in the back of my mind also says it's just five seconds. People tend to make that in to three or four though, if you tell them "hold it for five seconds", so I guess that's where the longer advices might come from.
However, lyceum, you seem to imply that not even a firmware flash helped? In that case I'm not too confident this will either, but well, it's worth a try of course.