I have a large Storage Drawer bank set up with a polymorph filter on the controller. All items that belong in there are in the filter with a priority of 10. Despite that a lot of items end up in a chest with a lower priority.
This does not happen consistently, but starts randomly. When I add other items to the polymorph filter it sorts correctly for some time.

Only Storage Drawers

Does this happen with any other storage besides storage drawers? I've been told that drawer controllers do weird things with their inventory, and thats probably the problem.