Given an array of droppers pointing into hoppers that point back into the droppers. If you power all of them with different redstone dusts on top of blocks on top of them, they behave unexpectedly. Depending on which redstone wire you power the system with, some droppers won't activate (they won't even make a sound when empty). When switching inputs from one dust to another, it will trigger the previous pattern the first time, then it will switch to the new pattern.

Interestingly, the F3 debug overlay says that the dropper that didn't fire is triggered, but one of the ones that did is not triggered. I assume this is the same issue as the rest of this, so that's why I added this in with the rest.

This is similar to the behavior of MC-11193 except in that one everything works, just out of order. In this one, the droppers just don't get powered.

(I've been able to confirm this as early as 1.6.4 so this might be due to a feature I'm blanking on...? If it is, I'm sorry for making you read this wall of text.)

The First image, Second image, and Third image all go consecutively (with unpowering the levers in between).

The Fourth image shows that it isn't a comparator issue, but instead the hopper actually never gets the item.

The Odd image shows the F3 triggered information of the dropper that fired.