How to FORCE plex to transcode from FLAC 24bit to MP3 when casting to a google cast group

maxi1134 · March 15, 2023, 2:22pm

Hey guys,
I am encountering an issue where anything but MP3 severely stutters on my google mini group.
There are 16 google minis and Youtube Music and Spotify work flawlessly on the group…

I’ve pinpointed the issue to high-bitrate FLACs but found no solution to force a transcode from FLAC to MP3.

Is this possible at all?

maxi1134 · March 15, 2023, 5:24pm

Update:

I’ve applied the following Chromecast.xml file:

<?xml version="1.0" encoding="utf-8"?>
<Client name="Chromecast">
  <TranscodeTargets>
    <VideoProfile protocol="http" container="mkv" codec="h264" audioCodec="aac,mp3" context="streaming" />
    <MusicProfile container="mkv" codec="opus" />
    <MusicProfile container="mp3" codec="mp3" />
    <PhotoProfile container="jpeg" />
    <SubtitleProfile container="ass" codec="ass" />
  </TranscodeTargets>
  <DirectPlayProfiles>
    <VideoProfile container="mkv" codec="mpeg1video,mpeg2video,mpeg4,h264,vp8,vp9,Hevc,h265" audioCodec="eac3,ac3,dca,aac,mp2,mp3,pcm" subtitleFormat="srt,ass" />
    <VideoProfile container="mp4,webm" codec="h264,mpeg4,Hevc,h265,vp8,vp9" audioCodec="eac3,ac3,dca,aac,mp2,mp3,pcm" subtitleFormat="srt,ass" />
    <MusicProfile container="mp3" codec="mp2,mp3" />
    <MusicProfile container="mp4" codec="eac3,ac3,dca,aac,mp2,mp3,pcm" />
    <MusicProfile container="ogg" codec="vorbis" />
    <PhotoProfile container="jpeg,gif,webp,png" />
    <SubtitleProfile container="ass" codec="ass" />
    <SubtitleProfile container="srt" codec="srt" />
  </DirectPlayProfiles>
  <CodecProfiles>
    <VideoCodec name="h265,Hevc,vp9">
      <Limitations>
        <UpperBound name="video.width" value="3840"/>
        <UpperBound name="video.height" value="2176"/>
		    <UpperBound name="video.bitrate" value="75000"/>
      </Limitations>
    </VideoCodec>
    <VideoCodec name="h264,mpeg4">
      <Limitations>
        <UpperBound name="video.width" value="3840"/>
        <UpperBound name="video.height" value="2176"/>
        <UpperBound name="video.bitrate" value="75000"/>
		    <UpperBound name="video.bitDepth" value="10" />
        <UpperBound name="video.level" value="42" />
      </Limitations>
    </VideoCodec>
    <VideoAudioCodec name="mp3">
      <Limitations>
        <UpperBound name="audio.channels" value="2" />
      </Limitations>
    </VideoAudioCodec>
    <VideoAudioCodec name="aac">
      <Limitations>
        <UpperBound name="audio.channels" value="2" />
      </Limitations>
    </VideoAudioCodec>
    <VideoAudioCodec name="ac3">
      <Limitations>
        <UpperBound name="audio.channels" value="6" />
      </Limitations>
    </VideoAudioCodec>
    <VideoAudioCodec name="eac3">
      <Limitations>
        <UpperBound name="audio.channels" value="6" />
      </Limitations>
    </VideoAudioCodec>
    <VideoAudioCodec name="dca">
      <Limitations>
        <UpperBound name="audio.channels" value="6" />
      </Limitations>
    </VideoAudioCodec>
  </CodecProfiles>
</Client>

But now get this error after the profile is loaded and I start a FLAC cast:

[Req#215d/Transcode] ClientProfileExtra: music transcode target already exists for streaming http

Anyone has an idea?

maxi1134 · March 16, 2023, 12:39am

Update 2:

I’ve added the

“” line with no luck.

It does show “[Req#7aad/Transcode] TranscodeUniversalRequest: using augmented profile Chromecast”, but it still plays in FLAC over 1411bps.

The complete file looks like this:

<?xml version="1.0" encoding="utf-8"?>
<Client name="Chromecast">
  <!-- Author: Plex Inc. -->
  <!-- Updated for Chromecast Ultra by ambroisemaupate. -->
  <TranscodeTargets>
    <VideoProfile protocol="http" container="mkv" codec="h264" audioCodec="aac,mp3" context="streaming" />
    <MusicProfile container="mkv" codec="opus" />
    <MusicProfile container="mp3" codec="mp3" />
    <PhotoProfile container="jpeg" />
    <SubtitleProfile container="ass" codec="ass" />
  </TranscodeTargets>
  <DirectPlayProfiles>
    <VideoProfile container="mkv" codec="mpeg1video,mpeg2video,mpeg4,h264,vp8,vp9,Hevc,h265" audioCodec="eac3,ac3,dca,aac,mp2,mp3,pcm" subtitleFormat="srt,ass" />
    <VideoProfile container="mp4,webm" codec="h264,mpeg4,Hevc,h265,vp8,vp9" audioCodec="eac3,ac3,dca,aac,mp2,mp3,pcm" subtitleFormat="srt,ass" />
    <MusicProfile container="mp3" codec="mp2,mp3" />
    <MusicProfile container="mp4" codec="eac3,ac3,dca,aac,mp2,mp3,pcm" />
    <MusicProfile container="ogg" codec="vorbis" />
    <PhotoProfile container="jpeg,gif,webp,png" />
    <SubtitleProfile container="ass" codec="ass" />
    <SubtitleProfile container="srt" codec="srt" />
  </DirectPlayProfiles>
  <CodecProfiles>
    <MusicCodec name="flac">
      <Limitations>
        <UpperBound name="audio.bitrate" value="1411" />
      </Limitations>
    </MusicCodec>
    <VideoCodec name="h265,Hevc,vp9">
      <Limitations>
        <UpperBound name="video.width" value="3840"/>
        <UpperBound name="video.height" value="2176"/>
                    <UpperBound name="video.bitrate" value="75000"/>
      </Limitations>
    </VideoCodec>
    <VideoCodec name="h264,mpeg4">
      <Limitations>
        <UpperBound name="video.width" value="3840"/>
        <UpperBound name="video.height" value="2176"/>
        <UpperBound name="video.bitrate" value="75000"/>
        <UpperBound name="video.bitDepth" value="10" />
        <UpperBound name="video.level" value="42" />
      </Limitations>
    </VideoCodec>
    <VideoAudioCodec name="mp3">
      <Limitations>
        <UpperBound name="audio.channels" value="2" />
      </Limitations>
    </VideoAudioCodec>
    <VideoAudioCodec name="aac">
      <Limitations>
        <UpperBound name="audio.channels" value="2" />
      </Limitations>
    </VideoAudioCodec>
    <VideoAudioCodec name="ac3">
      <Limitations>
        <UpperBound name="audio.channels" value="6" />
      </Limitations>
    </VideoAudioCodec>
    <VideoAudioCodec name="eac3">
      <Limitations>
        <UpperBound name="audio.channels" value="6" />
      </Limitations>
    </VideoAudioCodec>
    <VideoAudioCodec name="dca">
      <Limitations>
        <UpperBound name="audio.channels" value="6" />
      </Limitations>
    </VideoAudioCodec>
  </CodecProfiles>
</Client>

It would be great to be guided to documentation on profiles, as I cannot for the life of me find it unfortunately.

maxi1134 · March 16, 2023, 1:53pm

Update 3:

I tried adding the

    <MusicCodec name="*">
      <Limitations>
        <UpperBound name="audio.bitrate" value="320" />
        <UpperBound name="audio.channels" value="2" />
      </Limitations>
    </MusicCodec>

Part under “CodecProfiles” with no luck.

This is the final Chromecast.xml

<?xml version="1.0" encoding="utf-8"?>
<Client name="Chromecast">
  <!-- Author: Plex Inc. -->
  <!-- Updated for Chromecast Ultra by ambroisemaupate. -->
  <TranscodeTargets>
    <VideoProfile protocol="http" container="mkv" codec="h264" audioCodec="aac,mp3" context="streaming" />
    <MusicProfile container="mkv" codec="opus" />
    <PhotoProfile container="jpeg" />
    <SubtitleProfile container="ass" codec="ass" />
  </TranscodeTargets>
  <DirectPlayProfiles>
    <VideoProfile container="mkv" codec="mpeg1video,mpeg2video,mpeg4,h264,vp8,vp9,Hevc,h265" audioCodec="eac3,ac3,dca,aac,mp2,mp3,pcm" subtitleFormat="srt,ass" />
    <VideoProfile container="mp4,webm" codec="h264,mpeg4,Hevc,h265,vp8,vp9" audioCodec="eac3,ac3,dca,aac,mp2,mp3,pcm" subtitleFormat="srt,ass" />
    <MusicProfile container="mp3" codec="mp2,mp3" />
    <MusicProfile container="mp4" codec="eac3,ac3,dca,aac,mp2,mp3,pcm" />
    <MusicProfile container="ogg" codec="vorbis" />
    <PhotoProfile container="jpeg,gif,webp,png" />
    <SubtitleProfile container="ass" codec="ass" />
    <SubtitleProfile container="srt" codec="srt" />
  </DirectPlayProfiles>
  <CodecProfiles>
    <VideoCodec name="h265,Hevc,vp9">
      <Limitations>
        <UpperBound name="video.width" value="3840"/>
        <UpperBound name="video.height" value="2176"/>
                    <UpperBound name="video.bitrate" value="75000"/>
      </Limitations>
    </VideoCodec>
    <MusicCodec name="*">
      <Limitations>
        <UpperBound name="audio.bitrate" value="320" />
        <UpperBound name="audio.channels" value="2" />
      </Limitations>
    </MusicCodec>
    <VideoCodec name="h264,mpeg4">
      <Limitations>
        <UpperBound name="video.width" value="3840"/>
        <UpperBound name="video.height" value="2176"/>
        <UpperBound name="video.bitrate" value="75000"/>
                    <UpperBound name="video.bitDepth" value="10" />
        <UpperBound name="video.level" value="42" />
      </Limitations>
    </VideoCodec>
    <VideoAudioCodec name="mp3">
      <Limitations>
        <UpperBound name="audio.channels" value="2" />
      </Limitations>
    </VideoAudioCodec>
    <VideoAudioCodec name="aac">
      <Limitations>
        <UpperBound name="audio.channels" value="2" />
      </Limitations>
    </VideoAudioCodec>
    <VideoAudioCodec name="ac3">
      <Limitations>
        <UpperBound name="audio.channels" value="6" />
      </Limitations>
    </VideoAudioCodec>
    <VideoAudioCodec name="eac3">
      <Limitations>
        <UpperBound name="audio.channels" value="6" />
      </Limitations>
    </VideoAudioCodec>
    <VideoAudioCodec name="dca">
      <Limitations>
        <UpperBound name="audio.channels" value="6" />
      </Limitations>
    </VideoAudioCodec>
  </CodecProfiles>
</Client>

I get still the message saying that the Augmented profile is loaded, but I still get “[Req#6847/Transcode] ClientProfileExtra: music transcode target already exists for streaming http”

Could a plex employee please assist as these functions are not even documented?

maxi1134 · March 16, 2023, 2:07pm

Update 4: Some progress!

It seems like the Profile is being applied to videos:

But not to music.

maxi1134 · March 19, 2023, 2:57pm

Any help from an employee would be appreciated.

I didn’t want to go there, but I pay for this service and the support is non-existent.

maxi1134 · March 22, 2023, 5:08pm

I am adding a 30$ reward to whomever can help me!

system · June 20, 2023, 5:09pm

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How to FORCE plex to transcode from FLAC 24bit to MP3 when casting to a google cast group

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