This is visible when connecting a comparator to the drawer. Looking at DrawerBlock.java it appears you're multiplying the amount by 14 twice.

Functional Storage Version:
1.18.2-1.1.3

Titanium Version:
3.5.8

Same problem in 1.19.2 and when a External Storage from Refined Storage is attached to the Draw i can't get any items in or out and the the Items don't stack anymore.

Functional Storage Version:
functionalstorage-1.19.2-1.1.3

Titanium Version:
titanium-1.19.2-3.7.3-27

Modpack Version:
Direwold20 1.19 - 1,9,0