Minecraft 1.14.4, Fabric Loader 0.6.1, Tubular 1.1.1. Basically, the filters are hungry.

If I set up a network like this:

where the front chest is being pulled from by both of the chests on the side, it seems to work fine. But if I set a filter on them, like so:

it pulls only the stone blocks out and eats them. They don't end up in either of the receiving chests. The other blocks (retextured granite) are left alone.

The same thing seems to happen if I only set a filter on one. As soon as I remove the filter, both chests pull all the items as they should.

Here is a similar setup, this time with three connectors and a tube between.

The side chests are again pulling from the front one. Without filters, this works fine. With filters, one chest set to granite and one set to stone, however, it resumes eating items, both the granite and the stone this time.

If I set that same configuration to have one unfiltered and one filtered chest, the unfiltered chest pulls both items, and the filtered chest devours whatever the filter is set to.

Additionally, adding a filter item to the outgoing connector doesn't restrict the output.

In this setup (which also seems to have hungry filters), the chest has a filter for cobble on its open port, the barrel in the middle has a cobble filter on its pulling port, and the barrel on the right has no filter on the pulling port. I put a stack of granite and cobble in. Half the cobble got eaten, and the barrel on the right was able to pull out the other half of the cobble, plus all the granite, despite the chest's outgoing filter. (I'd have expected the granite to stay where it was and the cobble to be split between the barrels.)

Here is the log file from my testing.
latest.log

I realize this is kind of confusing to describe. I can put a private video up on YouTube if you want, demonstrating what I'm doing. I am running quite a few other mods, so if you suspect a mod conflict, please let me know and I'll see if I can narrow it down. Thanks!

This is happening to me too.
Any combination I try, whenever I add a filter on the requesting side, the network seem to eat all items.
Filters on the supply side does not work.
Also, the filter setting should be a ghost item. Right now, it's storing a real item.
This is tested between normal chests, because Stockpile does not work with tubes.
Version: MC 1.14.4
Mods: Tubular and Stockpile.

Correction: Output filter does work, it's just the input that is not working.
Since it's a real item in the filter and not a ghost item, it could be a nbt tag value that is not matched correctly (or ignored).