Create a small Corporea network. A single chest containing one type of item is all that’s needed.

Place two Corporea Funnels near to each other. Place them on the ground so that they toss items into the world rather than put them into an inventory. Configure both funnels to output the same item in response to the same redstone signal.

Place a Spectranthemum in range of both funnels. Bind it to a point a short distance away. Give it a mana pool to use.

Trigger the funnels. I see two items being tossed into the world followed by two puffs as they are grabbed by the Spectranthemum. The items were not close enough to merge into a single item stack.

Checking the input chest confirms that two items did get removed. But, most of the time, when I go to where the Spectranthemum dropped the items I only pick up one item and there is no sign of the second.

I say “most of the time” because occasionally both items do get sent. I ran some tests with stacks of items being moved 2 at a time in this way. 4 stacks of 64 items resulted in the following items being received at the other end - 39, 43, 33, 35

(Minecraft 1.7.10. Botania R1.6-180, Forge 10.13.2.1291, Baubles 1.0.1.10. No other mods.)

I've found a much simpler way to demonstrate this bug. All it needs is a single funnel tossing items into the world. The second funnel and the Spectranthemum are not needed.

Create a Corporea network with a single chest containing one type of item and a funnel configured to toss that item into the world. Set up a line of redstone so you can trigger the funnel from a short distance away without the items going into you inventory.

Trigger the funnel multiple times. Watch the items popping out as expected and then check the input chest to confirm that one item was removed for each time you triggered the funnel. Then go to collect the items. Every time I do that I end up with fewer items in my inventory than I would expect. It seems that any time I pick up two or more items at the same time, only one goes into my inventory.

This only seems to be a problem when the funnel puts the items directly into the world. If the funnel is above an open crate which drops the item then there is no item loss.

(Sorry I didn't make the original report simpler. I though I had reduced it as far as possible, but clearly not.)