Just to add to this thread as I’ve been experiencing the same sort of issues with edited replies appearing at the bottom of the thread and some other anomalies regarding posts being given strange “Reply to” post numbers (too inconsistent to reproduce).
All resolved for me by turning off the “Reply Threading” setting in Forums Settings. This also reactivated the paginating which hadn’t been working with this setting active.
Not running anything unusual although someone mentioned php version which I know not to be the latest on our server. Details below:
PHP Version: 5.2.5
Wordpress Version: 3.8.1
Active Theme: Twenty Fourteen 1.0
bbPress 2.5.3 (active)
BuddyPress 1.9.2 (active)
Disqus Comment System 2.74 (active)
Fourteen Colors 1.0.1 (active)
Jetpack by WordPress.com 2.8 (active)
Unconfirmed 1.2.3 (active)
WP Approve User 2.3 (active)
