It's looking like it's related to the mysql replication. The slave seems to be locking rows in the database on the master while it's copying records over. I'm seeing no issues whatsoever now that I turned off the slave server. The only downside is that the site will be down (freeze) for a few minutes when database backups are done. Like 3-4 minutes tops at 3AM.
I turned everything back on. I also adjusted the flood control to limit us to 4 seconds minimum between posts.