I have one thread on the psychotherapy forum that skips about 10 posts (a whole page just doesn't load and skips to the next page). Really odd. It is definitely skipping 10 posts because one page ends at post 320 and the next post/page that loads is 331.

ETA: It's a problem with the forum default for number of posts per page. I switched to 20/page and those posts showed. I switched back to forum default and they disappeared again. Never have had that happen before but at least I know how to get around it.