Dukkha has its source in the contingent nature of all things, including our "selves" which are contingent and therefore impermanent and therefore unsatisfactory (dukkha). It is craving for things to be permanent that causes the problem. If we didn't crave then there'd be no dukkha. How can we stop craving? By ending ignorance. Ignorance of what? Of the four noble truths and the first two are that there is dukkha, that dukkha has a source which is craving. When we understand how we cause our own suffering by craving, when we understand how it happens by craving things that are impermanent, when we really see this, craving comes to an end. Craving is the cause of our suffering and it is ended by ending ignorance; ignorance is the cause of our suffering. They are one and the same.
It's not *really* about craving for material goods, isn't it? It's craving for our relationship to things to be satisfying, to stay within our control, for impermanence to not affect them. It's larger than material goods. One can have material goods as long as we aren't craving them. (Kinda hard, I know.)