"When it happens to two good pilots in a good well maintained aircraft flying for a good company " ( quote Pace)
Thats a whole lot of "goods" Pace. Might be wiser to await the outcome of the investigation and then come to a view...things are often not as they might at first seem....particularly to those on the outside.
For what its worth I agree with Above the clouds and i think instrument failure perhaos a failed attitude indicator or blocked pitot giving false speed reading are the most likely explanation.....on the little information we presently have. i have to say that the view from locals is that maintenance issues may well be in focus....