Bulk Inserters only grabbing one item (no override)

[fryyyy]

I'm trouble shooting a friend's setup. Stack size is not being overridden. There are no circuit settings on the inserters. The inserters do not wait for a second item after grabbing the first. Even when the belt is saturated with one type of item, they still only grab one at a time. Why aren't these bulk inserters grabbing more than one item? Am I missing something obvious here? Is this a bug?

bulkinserter.jpg (232.44 KiB) Viewed 210 times

[Nosferatu]

Asteroid chunks have a stack size of 1.
You can never grab more of them

[fryyyy]

Perfect, thanks