Subtitle loading issues/字幕加载问题

[ysn2382617094wsw]

After loading the subtitles, the display of the subtitles doesn't match the sound of the media, it's always about 1-2 seconds late, the VTT files have been checked in the local Potplayer and there is no problem/加载字幕后，字幕的显示与媒体的声音无法匹配，总是晚1-2秒左右，VTT文件已在本地Potplayer检查，并没有问题

WEBVTT

00:00:53.250 --> 00:00:56.920
有时候我会突然醒来

00:00:57.880 --> 00:01:00.710
发现自己在流泪

The first sentence of the VTT file is at 00:00:53 but the subtitles start loading at around 00:00:51, why is that?/VTT文件第一句话是在00:00:53 但是字幕在00:00:51左右就开始加载了，这是为什么？

code and file.zip
Above is my index (plyr and hls) code, and the main m3u8 file, the 1080p sub m3u8 file, the subtitle m3u8 file, and the subtitle VTT file/上面的是我的index（plyr 和 hls）代码，和主m3u8文件、1080p分m3u8文件，字幕m3u8文件、和字幕VTT文件