This is not ASS specific issue. Happens to SRT too. (probably all subtitle formats)
I see the correct subtitle is auto picked before playing media.
Same for both embedded and external subtitles.
App version 2025.15.0 (966828394)
Server version 1.41.6.9685
2025.16.0 did not fix the problem
embedded both srt and ass, none of them showing when casting from android
@MIvanIsten This issue was about originally playback on android. not casting. What are you casting to?
To Chromecast 3
There is some progress with 2025.18.0
Subtitles showing when casting from android, but settings (size, color, etc) are ignored.
Moved this to a new topic since the other was about playing on android itself.
2025.19.0 did not fix, subtitle settings still ignored, also subtitles are shown with some weird monospaced font.
2025.20.0 did not fix.
2025.21.0 did not fix.
2025.25.0 still no fix.
Same problem with Chromecast Ultra… I want to update but the damage they’ve done…
2025.29.0 still no fix.
2026.1.0 still no fix.
2026.7.0 still no fix
2026.8.0 still no fix.
2026.14.1 still no fix (server version 1.43.3.10828-00f62d37d)
I’m surprised we’re still like this after all this time… I want to update to see if it’s more stable with my Chromecast Ultra and use the other features… but what a mess Plex has made…
The old app crashes quite a bit and is unstable to use. I’m still using version 10.26.0.2578 because even though it’s unstable and crashes a lot, all the subtitles work perfectly on Chromecast Ultra. 
Is there any progress on this?
Can confirm that ever since the new app (the redesign) casting from Plex to a Chromecast (the old kind without Google TV at least, I have an Ultra myself but friends using my server generally have the non-Ultra kind) subtitles seem to (almost?) always get converted to WEBVTT (from e.g. ASS), which also means they lose all of their styling and placement. This is especially annoying if you watch a lot of anime, which often uses heavily styled ASS subtitles. With the old app they were able to direct play these just fine, or they would get burned into the video if a transcode was necessary. I’d honestly be fine with having them burned in by default as well, as anything is better than losing all of the subtitle styles.
As said above it’s not just ASS subtitles, but SRT as well. Another downside of everything getting converted to WEBVTT is that it uses this ugly monospace font and that the subtitles get a black background. Subtitle style settings are completely ignored.
