mined diamonds not added to inventory

Using Fortune III enchanted pickaxe, harvested 3 block diamond vein, saw multiple diamonds drop per block, picked them all up, only added three to inventory.
Next time, had 9 block vein, saw multiple drops per block, only added 6 to inventory - from 24 to 30.
This bug has persisted over several game starts and reboots since last update.

Let me know if more information is needed