M18 - cooldowns on consumables

Noticed when I used my health stone that the cooldown didn't countdown as expected. It sat at 18s until I entered my character screen, or hit esc, alt tabbed out of the game... you get the idea.
Same happened for the altar.
These were the only consumables I noticed the problem with.
Chain of scales was counting down correctly.
I would bring up my character screen during combat to check the cooldown on my health stone, 4s, and it would stop counting.