Facebook, how the button shows incorrectly, how the score (very low some periods)

I am using the new Facebook button as / share on the website.

I am using the HTML5 version, the url is always the same (only http no https and only used on the homepage). So not different urls at all.

Everything works great with sympathy / sharing, but the similar amount is really really strange. It seems that such a count hesitates like a madman. Yesterday the page liked 76, but this morning there are only 6 left. The site has done this for the last couple of days. Show the correct number of hours for a few hours and then a very low number (4 or 6 I think) to get back to the correct amount after a couple of hours.

At first I thought it was some kind of caching issue on the facebooks side, but this has happened in the last few days and I can't figure out why.

https://graph.facebook.com/http://example.com always shows the correct amount, even if there is no HTML output in the site. Very strange.

Any idea what might be causing this, or if anything I can do bump into it?