What's going on with the upvote count on the front page?

I've been watching our top posts and the number of upvotes seems to be going down. I thought this might be because of downvotes, but I tried it out on a few of my own posts and I found that I've been downvoted twice and I had 4 less upvotes than before. I can see myself downvoting my own posts and I can see no upvotes, but that's all. I can't see any downvotes and I don't think there should be any. This seems to be happening with every post and I can't find any other subs with this issue.<br><br>We're not a normal sub and we might be different in some ways, but this is unusual.