Ok, I enabled logging, then navigated to the movie, started it and after I saw the first subtitle I moved to position about 0h:53min. Subs were still working. Then I moved to position 1h:15min and ... no subtitles.
I went through the log a bit and I think Kodi loads the whole subtitle file at once at the beginning. So I guess the problem is somewhere in Kodi..
It seems Serviio creates log files 500KB each. I'm attaching the one that corresponds to the timespan I conducted the experiment.
11.12 is Kodi box, 11.13 is the server with Serviio.
The file is protected, I'm gonna send you the password as a PM. Edit: Ok, It seems I can't use PMs, anyway. If interested, I can send the PW in some other way.
As to beta testing, I don't know, the TV box is Android and I'm no that fond of trying things on Android that I can't easily revert (the same on my smartphone(s)). If you have strong evidence you found the culprit (and it is Serviio's fault), and cannot test, I probably can test in some VM.
P.S. Hm, it seems I was confused. Serviio is not running on the TV box but under Windows. I thought of Kodi when speaking about testing on my TV box
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