[PharmaDrMan]

The 1st level is the inherent dukkha due to impermanence

But you said dhukka lakkana is to be observed (vipassana insight) independent of the impermanence quality of phenomena in a previous thread. Because the Buddha taught them as three inherent qualities, not two. I always understood unsatisfactoriness in terms of anicca as your computer simile shows. I just don't understand how it stands as one quality on its own without dragging impermanence to the picture. It's hard to explain; Hope you get what I mean here