Plex no longer transcodes

Plex Media Server NAS & Devices
8

Edit:

  • This applies to both 1.40.3.8555 and 1.40.4.8598.
  • Workaround is to fall back to an earlier version, but not before 1.31.2 due to database changes.
  • Synology does not permit direct fallback. You must uninstall the current version first, then install the older version. When uninstalling, choose the “Uninstall Only” option.

Were you trying to transcode HDR media?

There is a problem with HDR tone mapping. With HDR Tone Mapping enabled, Plex Media Server falls back to software decoding. The CPU is not strong enough to perform the task in software, so playback fails.

This affects devices with the Gemini Lake CPUs, such as the DS920+, and Apollo Lake CPUs, such as the DS918+.

Hardware accelerated transcoding of H.264/1080p/SDR video should not be affected (It works OK on my DS918+).

Monitor this thread for updates: HDR Tone Mapping not compatible with HW Accelerated transcoding anymore (DS920+)