I've looked at multiple reasons why it happens (and every finger points to something else lol.) I've found that editing my photos or cropping them, then resaving fixes the problem when it DOES happen to me (it's intermittent.)
When we upgrade to the latest version of the forum software (which is coming sooner than later,) if we still see it happening I've already researched a solution for it (letting members rotate pictures themselves when placing the pictures.) Tomorrow's maintenance is the hopeful flip to the new hardware and provider. Once that's solid, we begin dev on the new software version. It's the same software we're using (just upgraded,) so the development part will just be getting the current state of AFN setup for the latest version (and the newest/latest version is friggin sweet, I'm playing with it right now and it's like naked cherubic angels are singing somewhere over mysterious formed bright clouds as I click on things.)