A customized Plex profile for the Nvidia Shield, which goes in ./Library/Application Support/Plex Media Server/Profiles/

Android-SHIELD Android TV.xml

<!-- Put in ./Library/Application Support/Plex Media Server/Profiles/Android-SHIELD Android TV.xml -->
<!-- Author: Donald Webster [email protected] -->
<?xml version="1.0" encoding="utf-8"?>
<Client name="SHIELD Android TV">
  <Identification>
    <Header name="User-Agent" substring="SHIELD Android TV" />
  </Identification>
  <TranscodeTargets>
    <VideoProfile container="mkv" codec="h264" audioCodec="aac" context="streaming" />
    <MusicProfile container="flac" codec="flac" id="StereoMusicTranscodeProfile" />
    <PhotoProfile container="jpeg" />
  </TranscodeTargets>
  <DirectPlayProfiles>
    <VideoProfile container="mkv" codec="vp9,hevc,h265,mpeg1video,mpeg2video,h264,mpeg4" audioCodec="eac3,ac3,aac,mp3,mp2,pcm,flac,alac,truehd,dca" subtitleFormat="srt,ass,smi,ssa,subrip,pgs"/>
    <VideoProfile container="mp4" codec="hevc,h265,mpeg1video,mpeg2video,h264,mpeg4" audioCodec="eac3,ac3,aac,mp3,mp2,pcm,flac,alac,truehd,dca" subtitleCodec="srt,ass,smi,ssa,subrip,pgs"/>
    <VideoProfile container="asf" codec="wmv3,wmv3,vc1" audioCodec="wmav2,wmav2,wmapro,wmavoice,pcm" subtitleCodec="srt,ass,smi,ssa,subrip,pgs"/>
    <VideoProfile container="avi" codec="h264,msmpeg4v3,mpeg4,mjpeg" audioCodec="mp3,ac3,eac3,dca,pcm" subtitleCodec="srt,ass,smi,ssa,subrip,pgs"/>
    <VideoProfile container="mpeg" codec="h264,mpeg1video,mpeg2video" audioCodec="mp2,mp3,ac3,eac3,aac,pcm" subtitleCodec="srt,ass,smi,ssa,subrip,pgs"/>
    <VideoProfile container="flv" codec="h264" audioCodec="aac,ac3,eac3,mp3,pcm" subtitleCodec="srt,ass,smi,ssa,subrip,pgs"/>
    <VideoProfile container="mpegts" codec="h264,mpeg2video,vc1" audioCodec="mp2,mp3,ac3,eac3,dca,pcm" subtitleCodec="srt,ass,smi,ssa,subrip,pgs"/>
    <VideoProfile container="wtv" codec="mpeg2video" audioCodec="ac3,eac3,aac,pcm"/>
    <VideoProfile container="3gpp" codec="h264,mpeg4" audioCodec="aac,he-aac"/>
    <MusicProfile container="mp4" codec="aac" />
    <MusicProfile container="mp3" codec="mp2,mp3" />
    <MusicProfile container="flac" codec="flac" />
    <MusicProfile container="ogg" codec="vorbis" />
    <MusicProfile container="ac3" codec="ac3"/>
    <MusicProfile container="wav" codec="pcm"/>
    <PhotoProfile container="jpeg,gif,bmp,png" />
  </DirectPlayProfiles>
  <ContainerProfiles>
    <VideoContainer name="mp4">
      <Limitations>
        <Match name="part.optimizedForStreaming" value="1" />
      </Limitations>
    </VideoContainer>
  </ContainerProfiles>
  <CodecProfiles>
    <VideoCodec name="*">
      <Limitations>
        <UpperBound name="video.width" value="3840" isRequired="true" />
        <UpperBound name="video.height" value="2160" isRequired="true" />
        <UpperBound name="video.bitDepth" value="10" />
      </Limitations>
    </VideoCodec>
    <VideoCodec name="h264">
      <Limitations>
        <Match name="video.profile" list="baseline|main|high" />
      </Limitations>
    </VideoCodec>
    <VideoAudioCodec name="aac">
      <Limitations>
        <UpperBound name="audio.channels" value="8" />
      </Limitations>
    </VideoAudioCodec>
  </CodecProfiles>
</Client>

On Asustor NAS it belongs in /volume1/Plex/Library/Plex Media Server/Profiles

On Synology DSM 7 it belongs in /volume1/PlexMediaServer/Library/Application Support/Plex Media Server/Profiles

On Synology DSM 6 it belongs in /volume1/Plex/Library/Application Support/Plex Media Server/Profiles

Looks like MIKE CONNELLY's