Okay, I have a real weird one. It might be a little hard to explain in words. Please bear with me. I've done some web searches for this issue already, but it's hard to search for and ends up turning up very general, common issues.
I'm watching an mkv file (anime episode) with 3 chapters (opening, episode, and ending) and a subtitle track. VLC is exhibiting strange behavior regarding these. When I open the file, it plays as normal, with subtitles over the opening music, until it reaches the end of the 'opening' chapter and the episode begins. At this point, the progress bar skips about a minute and a half forwards. The progress bar will continue to move forward at its usual rate, and then at the beginning of the 'ending' chapter it will have reached the end of the progress bar. (The ending will playback as normal, it's just that the bar is visually ahead of where it should be.) Additionally, and much more annoyingly, when this initial skip occurs, it turns off the subtitles. If I manually turn the subtitles back on, and go back to the opening chapter, subtitles will be disabled in the opening!
So, in other words, enabling subtitles in one chapter will disable subtitles in the other. It's like whack-a-mole. It means that whenever I access this file, I have to let the opening play, and then go into the settings to enable subtitles again, as they're automatically enabled during the opening chapter, and therefore automatically disabled in the actual episode itself. I looked at the mkv file a bit using MediaInfo and MKVToolNix, but I don't have enough expertise to determine whether there's an issue in file formatting I can fix. Is there anything I can do to make the subtitles automatically enabled for all chapters, so enabling them in one chapter doesn't disable them in the other? Subtitles are already auto-enabled in VLC settings, but they auto disable the other chapters anyway, for some reason. The progress bar issue is tolerable, and honestly at this point I would settle for if anyone knows a hotkey to enable subtitles so I don't have to go into the menu every time.