Ask HN: Karma not adding up

Hi all,

Not sure if this is the right forum for it, but since about last week, I've noticed that my karma points do not seem to be updating correctly, based on a couple of posts and upvotes (no downvotes that I'm aware of). So far, I can't find any pattern in how it does or does not go up.

Is there anything in the karma system that I'm missing?