SPACES REMOVED after punctuation in 3.6.7

I'm using 3.6.7 for my client's site, www.miningtheunconscious.org.

Despite all looking well in both the code and visual editor, the live site is removing or not displaying the spaces following commas, ampersands and so on, including in the navigation bar and page title (words that are typed in, not pasted from client copy).

I can't figure out why or how to fix it (for instance, retyping copy directly into the code view - not pasting; attempting to add extra spaces, making sure pasted copy is clean - but you'll see it in the footer, too...).

As ever, the code view in WP definitely doesn't show all code. I feel hamstrung! Anyone else encounter this and/or know the fix for it? I'm really not interested in going in and coding NBSPs all over the place...

I also posted this in the WP.org forum but have only encountered another user with the same problem - no answers.

Thanks!