Bug Report: Chinese external ASS subtitles display abnormally on Emby for Apple TV

[phoesky 0]

Device Model: Apple TV 4K (2022, 7th Generation)

 

OS Version: tvOS 26.4 & 26.5

 

Emby App Version: 2.0.6

 

Issue Description

 

Chinese ASS‑format subtitles (external or embedded) have failed to display properly over the past few days. Chinese characters appear as empty boxes (see Figure 1), and video playback stutters severely. Playback works normally when no subtitles are enabled, or when English/Japanese subtitles are used.

 

 

 

 

1. The issue occurs across all videos with external or embedded Chinese ASS subtitles, not just a single file.
2. This problem has never happened in the past two years. I suspect it is related to the automatic tvOS 26.4 update. The issue persists after manually upgrading to tvOS 26.5.
3. An important observation: If I exit playback and restart repeatedly, subtitles occasionally return to normal. However, the problem reappears automatically when playing the next episode.

4.Log information: No server‑side logs are generated when streaming via the Emby app on Apple TV. I have checked thoroughly and cannot provide logs for this issue.

5.Other Apple TV media players such as Infuse play the same video files without any subtitle‑related issues.

 

[phoesky 0]

PS: All problematic subtitles so far are Simplified Chinese. I have not tried playing Traditional Chinese subtitles for the time being.

[phoesky 0]

OK, Now I found a log file

ffmpeg-transcode-5bc050a1-7683-472c-b664-bdd6166e85ba_1.txt