Hopper attached to Compressor's top face destroys ingots

[EzerArch]

Minecraft version: 1.12.2 Galacticraft version: 280

Single player (SP), Multiplayer (MP), or SP opened to LAN (LAN)? SP

Any Galacticraft add-ons installed? No

1. Place ingots in the hopper attached to Compressor's top face;
2. 1-2 ingots disappears. The remained ingot is placed randomly in the grid.

Since the Compressor has a 3x3 grid and a variety of shaped recipe, I think hoppers should be disabled.