[SOLVED] Media player in lister using LAV fails to play MKV/MP4 with AV1 video stream

[Flint]

Yes, they start with BOM; and yes, they are real SRT. They don't have any file extension, since they are not files but just embedded tracks. To check the contents I extracted them via mkvextract.

[ghisler(Author)]

Here the subs filter from these dlls refuses to connect to the video renderer, and reports an unsupported format. XySubFilter.dll does not have any output pins, it passes the subs only to very specialized video renderers which I cannot use. So my guess is that they didn't update the video output pin in the VSFilter.dll to support srt, or there is a bug.

The subs which didn't work here also indicated Unicode text content.