I have numerous Star Trek TV episodes saved on my hard drive - VOB files. I play them with my VLC media player. I have no problem loading the subtitle (Spanish) files onto the show. Most will play until I get to the introductory credits. After the credits and the show resumes, there usually aren't any subtitles. Or they will show up out of the blue here and there, mostly out of sync. The puzzling thing is that when I play downloaded files by "youngdangerous" (listed in the file name), 95% of the time they will play perfectly. I can pause. Jump forward. Go back. Whatever I do, they still play in sync. I've downloaded some individual episode subtitles numerous times (6-10) from different sites but none will work. Except for "youngdangerous" of course, but don't have the subtitles for all the episodes. I'm not very knowledgeable about things like this but I'm able to get all the srt. subtitles into text format. When I do that, I can see that all are synced to a certain time frame. All of the ones look exactly like the ones form "youngdangerous". So I'm not sure why only that one works.
You mean they are in a VIDEO_TS folder with the .IFO and .BUP files? If they are timed properly from sources that are the same frame rate as your video, they should play 100%. Generally, you start VLC and load the video file, then pause the video playback and load the .srt file. The .srt file should immediately line up with the video (even if you missed the first few subs).