Hi Bec.

I think this is a hosting issue. What host are you using and when you installed Wordpress did you have to do it manually, or with your host's one-lick script? Like Fantastico etc.

I always install manually and even set up the database myself. I don't trust CPanel for some things because they've screwed things up royally in the past.

So yeah. I think this has something to do with the connection to your host. I had this issue when I was with Certified Hosting. Only with a few blogs though. It was odd. I'm with Host Gator now and don't experience the problem with them.