Kodi plays the source but Plex for Kodi struggles



I'm playing a 4k h265, dolby-hd file via the following methods:
1. Plex for Android - transcodes due to unsupported audio codec
2. Plex for Kodi - seems to be transcoding as well, cannot keep up with video.
3. Kodi over SMB share - plays with no issues.

I'm most curious about why I'm having issues with Plex for Kodi. If it's just using the internal Kodi player, shouldn't it have played the same way as using Kodi directly?
I should also mention that I my system only includes the Nvidia Shield and a TV. I don't have any audio equipment and it's probably safe to assume the TV doesn't support dolby-hd or multi-channel audio.


Have you enabled HEVC in Plex for Kodi options?