only 6 points? Not a big deal. My hub score typically ranges from 94-97 when I am on here everyday. But yesterday it dropped to 93, and today its 98. As long as it is above 70 you're just fine.
I don't really worry about it because there are quite a few factors involved in determining the score, including some random variability I believe.
If you want to try to get your score up, there are a few things you can do that will probably help, although it is hard to know exactly what has an affect on the hubscore.
Try going into the forums and responding to a few posts there. Then read through some new hubs from your followers and comment on the ones you like. Maybe even try the hub hopper. Also take a look at your hubs and maybe edit the ones with low scores adding more pictures, info or links to related stuff.
Hope this helps, but don't stress about your hubscore, it naturally changes quite a bit.