Yes, the ASS subtitles do cause the video and audio to be transcoded, so perhaps transcoding is the common denominator. I’ll have to find another video that transcodes for some other reason to verify this.
FWIW, here is a link to another thread that deals with this same problem. It doesn’t appear anything is being done. TBH, I’m getting a bit tired of reporting stuff like this, knowing I can replicate the problem at will, and not seeing any useful response.
