I have all the subtitles timed correctly on my .srt. The timecodes (ex, 01:40:34,841 --> 01:40:37,319) correspond to the video no problem. However, after authoring with ifoedit, tbe subtitles are okay for about 45 minutes or so or so, then a delay starts to happen and after about an hour or an hour and a half, the timing becomes gradually off (the subtitles start appearing about a second early, then 2, 3, 4 seconds, etc) It's really strange because on the srt, there is no such problem. I use txt2sup for the conversion, but I doubt that's the problem. Anyone has an idea what the problem is?