What speech reader do you use? I've been using a free version to check chapters for obvious missteps (easy to miss an "of" reading to yourself; not as easy to miss a missing one when someone is reading it aloud).
I use iSpeak it for Macs. It's great for proofing as you are using a text reader for. I can usually find the obvious missteps that don't get picked up. I've had a couple of people have me listen to their stuff to catch them too.