While playing the movie on the Samsung, check playback status with the Plex Dashboard. It will tell you if the video, audio, or both are transcoding. If necessary, toggle the button on the top right to see expanded, per-track information.
The Plex app for Samsung Tizen TVs has limitations compared to other Plex clients:
- Enabling PGS or VOBSUB subtitles results in a video transcode.
- If the audio is transcoding, enabling SRT subtitles results in a video transcode.
- TrueHD and dts audio will transcode, as Samsung does not license those codecs. Dolby Digital (AC-3) and Dolby Digital Plus (EAC-3) should direct play.
Samsung TVs have a limit on the number of supported tracks in a stream (either 20 or 25).
Samsung TVs support a maximum of 30 tracks in a stream. If your media file has many audio and video tracks, consider removing the unnecessary tracks. MKVToolNix is a good, free tool for remuxing files. The output is a MKV file, but it can accept other file formats as inputs.
Edit: Samsung TVs have a limit of 80 Mbps for HEVC/H.265 video and 60 Mbps for AVC/H.264 video. If the limit is exceeded, Plex will transcode the video.
See this post for additional information on stream and bandwidth limits.
