On my woodland 8H, I sometimes had problems clogging the chute when the
chipper would bog down or the belts would slip. If the airflow was high, I never had an issue. I did have an issue on the edge of the flywheel, when chipping pine, where pitch and shavings would stick between the flywheel and the housing. That would cause it to smoke and slip the belts much easier. My solution was to put a couple weld beads perpendicular to the flyweel on its edge, such that the weld bead would sweep out anything and prevent it from acting like a brake. Before doing that mod, sometimes I would dump a little diesel in, which would work for a little bit but not long term.
So a couple things to check. One is to make sure that you aren't having clogging issues somewhere other than the chute, which might lead to the chute getting clogged. The next thing is to make sure you're operating at a high enough rpm to have adequate airflow.
It would also make sense that smaller chutes are going to get stickier faster than larger chutes. This will be worse when you're not making many big chips to blast the surface clean.