Lost Connection on new post of the main website in WPMU

I have tried the WordPress forums to no avail. It continues to be a rather big problem, so I am hoping someone might have a thought here.

My main website (geekazine.com) has a big problem when I post a new article to it. The Edit page will eventually say “Connection Lost with host”. I can’t do anything with the new post until it comes back. If I try to save the post, sometimes it will bring the whole system down – either getting a 503 or 500 error.

Here is the kicker: All other child sites not only run and post perfect, they continue to work even though this post comes back with errors.

I have had this issue for a few months now. Disabled all plugins and cleared the cache. Flushed and changed the Theme. I have played with .htaccess and wp-config.php multiple times. Everything is back to Network suggested settings.

Someone suggested MySQL might be crashing, so I went into the DB to find anything that could do something like that. I have yet to find what it could be.

So I am at a complete loss. How is it the main site can crash, and the other child WP sites continue on without problem?