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There has been considerable work on active matter or self-propelled systems which exhibit an interesting mobility-induced transition as a function of increasing activity; however, far less is known about how these systems behave in the presence of random disorder. Here we show that in the presence of random obstacle arrays, the active matter system show a non-monotonic susceptibility to becoming jammed as a function of activity.  At low activity, the system can form a jammed state similar to that found in granular systems. At finite activity, a fluid-like state appears that can flow easily through the disorder;  however, when the activity is large, the system enters a motility-induced phase separated state which can induce a transition between easy flow and a jamming or clogging of the active particles.  Within the actively clogged state, motion occurs in the form of avalanches that have a power law size distribution,  suggesting that the system has reached a critical state similar to that at point J found in non-active granular systems that undergo jamming.