Playlist Auto Advancing working intermittently

All of my streaming videos utilize a 7 second pre-roll and post-roll clip that shows my organization's logo, so we use a playlist for all media files. Occasionally, I've found that JWplayer does not properly auto-advance to the actual video. The problem seems intermittent; sometimes it will auto-advance if the back button is pressed and the pre-roll plays through again, other times it will not. It usually works in Chrome, but not Firefox. Only the pre-roll seems to have trouble auto-advancing. I'm using repeat=list, but repeat=true doesn't work either.

I'm using apache's mod_flv to for seeking and stream=lighttpd as a flashvar, if that has anything to do with it.

Please see http://www.rpitv.org/vod/ . Any production should have this problems, regardless of whether or not a playlist is show on the right.