Help understanding why CPU is being maxed out to transcode some files

[mrrichardcranium]

I think I see the problem, I don't know why it is happening.  Tell me if you spot the problem.

Code:

/usr/lib/jellyfin-ffmpeg/ffmpeg -analyzeduration 200M -probesize 1G -f matroska -init_hw_device vaapi=va:,vendor_id=0x8086,driver=iHD -init_hw_device qsv=qs@va -filter_hw_device qs -i file:"/mount/smb/Movies/Play Dead (2025)/Play Dead (2025) Bluray-1080p.mkv" -map_metadata -1 -map_chapters -1 -threads 0 -sn  -copyts -avoid_negative_ts disabled -max_muxing_queue_size 2048 -f hls -max_delay 5000000 -hls_time 3 -hls_segment_type fmp4 -hls_fmp4_init_filename "6f076b714ded0aba585565b0137c0fca-1.mp4" -start_number 0 -hls_base_url "hls/6f076b714ded0aba585565b0137c0fca/" -hls_segment_filename "/var/lib/jellyfin/transcodes/6f076b714ded0aba585565b0137c0fca%d.mp4" -hls_playlist_type event -hls_list_size 0 -y "/var/lib/jellyfin/transcodes/6f076b714ded0aba585565b0137c0fca.m3u8"

Don't see it?  Let me narrow down where it is.

Code:

-map_chapters -1 -threads 0 -sn  -copyts -avoid_negative_ts disabled

For whatever reason, there is a double space after -sn.  I am pretty sure that -sn is supposed to be followed by a bunch of filter and encoding parameters.  But, for whatever reason, that failed to generate within Jellyfin and ffmpeg just defaults to libx264 and aac.

I recall seeing this before, but can't remember the solution off the top of my head.  I'll search and ask around for the solution.

---

******EDIT*******

Can you share the contents of /etc/jellyfin/encoding.xml?

Got that here: https://pastebin.com/9qaiBr5g

[TheDreadPirate]

Some transcoding recommendations. I don't think these will fix the problem, but you'll be better off when we do with these settings.

- At the top, UNcheck mpeg4
- Enable variable bit rate audio
- Disable VPP tone mapping. While faster, the picture quality is quite a bit worse, IMO. (only applies for HDR to SDR tone mapping)
- Set the Encoding Preset to very slow

---

A couple more things.  Can you check that your motherboards BIOS are fully up to date and whether enabling ReBAR is an available option in your BIOS.

Also, read my guide linked below and check how old your GPU's firmware version is.  You don't have to update it, but I just want to make sure it isn't SUPER old.

https://forum.jellyfin.org/t-flash-intel...e-in-linux

Not sure if you missed this post.

[mrrichardcranium]

Some transcoding recommendations.  I don't think these will fix the problem, but you'll be better off when we do with these settings.

- At the top, UNcheck mpeg4
- Enable variable bit rate audio
- Disable VPP tone mapping.  While faster, the picture quality is quite a bit worse, IMO.  (only applies for HDR to SDR tone mapping)
- Set the Encoding Preset to very slow

---

A couple more things.  Can you check that your motherboards BIOS are fully up to date and whether enabling ReBAR is an available option in your BIOS.

Also, read my guide linked below and check how old your GPU's firmware version is.  You don't have to update it, but I just want to make sure it isn't SUPER old.

https://forum.jellyfin.org/t-flash-intel...e-in-linux

Not sure if you missed this post.

Appreciate the recommendations! Thank you.

No ReBAR settings for my platform as far as I can tell, last update was 2018. The GPU firmware is about 3 years old at this point: DG02_2.2339. Definitely time for an update.

[TheDreadPirate]

One of our devs looked at your ffmpeg log and noticed that the MediaStreams field in the ffmpeg log is empty, which it should contain the codec information. Did you have issues scanning your library initially? Can you run a library scan and once it completes share the main jellyfin log via pastebin?

[mrrichardcranium]

One of our devs looked at your ffmpeg log and noticed that the MediaStreams field in the ffmpeg log is empty, which it should contain the codec information.  Did you have issues scanning your library initially?  Can you run a library scan and once it completes share the main jellyfin log via pastebin?

I hadn't noticed any problems during setup, or really any time since then. I ran a scan and have the logs. https://pastebin.com/yZcTwiPH

[TheDreadPirate]

Something weird is going on with your setup. I see this regularly and I am pretty sure it is related.

Code:

[2026-07-09 05:55:43.491 -07:00] [ERR] Error in "Probe Provider"
System.Text.Json.JsonException: The input does not contain any JSON tokens. Expected the input to start with a valid JSON token, when isFinalBlock is true. Path: $ | LineNumber: 0 | BytePositionInLine: 0.
---> System.Text.Json.JsonReaderException: The input does not contain any JSON tokens. Expected the input to start with a valid JSON token, when isFinalBlock is true. LineNumber: 0 | BytePositionInLine: 0.
   at System.Text.Json.ThrowHelper.ThrowJsonReaderException(Utf8JsonReader& json, ExceptionResource resource, Byte nextByte, ReadOnlySpan`1 bytes)
   at System.Text.Json.Serialization.JsonConverter`1.ReadCore(Utf8JsonReader& reader, T& value, JsonSerializerOptions options, ReadStack& state)
   --- End of inner exception stack trace ---
   at System.Text.Json.ThrowHelper.ReThrowWithPath(ReadStack& state, JsonReaderException ex)
   at System.Text.Json.Serialization.JsonConverter`1.ReadCore(Utf8JsonReader& reader, T& value, JsonSerializerOptions options, ReadStack& state)
   at System.Text.Json.Serialization.Metadata.JsonTypeInfo`1.DeserializeAsync(Stream utf8Json, CancellationToken cancellationToken)
   at MediaBrowser.MediaEncoding.Encoder.MediaEncoder.GetMediaInfoInternal(String inputPath, String primaryPath, MediaProtocol protocol, Boolean extractChapters, String probeSizeArgument, Boolean isAudio, Nullable`1 videoType, CancellationToken cancellationToken)
   at MediaBrowser.MediaEncoding.Encoder.MediaEncoder.GetMediaInfoInternal(String inputPath, String primaryPath, MediaProtocol protocol, Boolean extractChapters, String probeSizeArgument, Boolean isAudio, Nullable`1 videoType, CancellationToken cancellationToken)
   at MediaBrowser.Providers.MediaInfo.FFProbeVideoInfo.ProbeVideo[T](T item, MetadataRefreshOptions options, CancellationToken cancellationToken)
   at MediaBrowser.Providers.Manager.MetadataService`2.RunCustomProvider(ICustomMetadataProvider`1 provider, TItemType item, String logName, MetadataRefreshOptions options, RefreshResult refreshResult, CancellationToken cancellationToken)

What plugins do you have installed?

We can also try reinstalling jellyfin to make sure none of the core files are corrupt or something.

Code:

sudo systemctl stop jellyfin
sudo cp -Rp /var/lib/jellyfin /var/lib/jellyfinBackup
sudo apt install --reinstall jellyfin-server jellyfin-web jellyfin-ffmpeg7

[mrrichardcranium]

Something weird is going on with your setup.  I see this regularly and I am pretty sure it is related.

Code:

[2026-07-09 05:55:43.491 -07:00] [ERR] Error in "Probe Provider"
System.Text.Json.JsonException: The input does not contain any JSON tokens. Expected the input to start with a valid JSON token, when isFinalBlock is true. Path: $ | LineNumber: 0 | BytePositionInLine: 0.
---> System.Text.Json.JsonReaderException: The input does not contain any JSON tokens. Expected the input to start with a valid JSON token, when isFinalBlock is true. LineNumber: 0 | BytePositionInLine: 0.
  at System.Text.Json.ThrowHelper.ThrowJsonReaderException(Utf8JsonReader& json, ExceptionResource resource, Byte nextByte, ReadOnlySpan`1 bytes)
  at System.Text.Json.Serialization.JsonConverter`1.ReadCore(Utf8JsonReader& reader, T& value, JsonSerializerOptions options, ReadStack& state)
  --- End of inner exception stack trace ---
  at System.Text.Json.ThrowHelper.ReThrowWithPath(ReadStack& state, JsonReaderException ex)
  at System.Text.Json.Serialization.JsonConverter`1.ReadCore(Utf8JsonReader& reader, T& value, JsonSerializerOptions options, ReadStack& state)
  at System.Text.Json.Serialization.Metadata.JsonTypeInfo`1.DeserializeAsync(Stream utf8Json, CancellationToken cancellationToken)
  at MediaBrowser.MediaEncoding.Encoder.MediaEncoder.GetMediaInfoInternal(String inputPath, String primaryPath, MediaProtocol protocol, Boolean extractChapters, String probeSizeArgument, Boolean isAudio, Nullable`1 videoType, CancellationToken cancellationToken)
  at MediaBrowser.MediaEncoding.Encoder.MediaEncoder.GetMediaInfoInternal(String inputPath, String primaryPath, MediaProtocol protocol, Boolean extractChapters, String probeSizeArgument, Boolean isAudio, Nullable`1 videoType, CancellationToken cancellationToken)
  at MediaBrowser.Providers.MediaInfo.FFProbeVideoInfo.ProbeVideo[T](T item, MetadataRefreshOptions options, CancellationToken cancellationToken)
  at MediaBrowser.Providers.Manager.MetadataService`2.RunCustomProvider(ICustomMetadataProvider`1 provider, TItemType item, String logName, MetadataRefreshOptions options, RefreshResult refreshResult, CancellationToken cancellationToken)

What plugins do you have installed?

We can also try reinstalling jellyfin to make sure none of the core files are corrupt or something.

Code:

sudo systemctl stop jellyfin
sudo cp -Rp /var/lib/jellyfin /var/lib/jellyfinBackup
sudo apt install --reinstall jellyfin-server jellyfin-web jellyfin-ffmpeg7

Plugins currently are: 

• AudioDB
  
• MusicBrainz
  
• OMDb
  
• Studio Images
  
• TMDb
  

User added:

• InfuseSync
  
• Moonfin
  
• Streamyfin
  
• Trakt
  
• Webhook
  

After reinstalling, scanning the library and attempting playback on the affected files it appears to be the same. Same JSON exception, and same playback problem.

[TheDreadPirate]

Run this command and share the output.

Code:

id jellyfin
sudo grep i915 /var/log/dmesg* > /tmp/i915.log

[mrrichardcranium]

Run this command and share the output.

Code:

id jellyfin
sudo grep i915 /var/log/dmesg* > /tmp/i915.log

Code:

➜  ~ id jellyfin
uid=112(jellyfin) gid=110(jellyfin) groups=110(jellyfin),44(video),993(render)

And for the dmesg log: https://pastebin.com/GiyrVbWi

[TheDreadPirate]

Code:

/var/log/dmesg:[    7.011293] kernel: mei_gsc i915.mei-gscfi.768: cl:host=01 me=33 fw disconnect request received
/var/log/dmesg:[    7.011323] kernel: mei i915.mei-gscfi.768-e2c2afa2-3817-4d19-9d95-06b16b588a5d: Could not read FW version ret = -19
/var/log/dmesg:[    7.011325] kernel: mei i915.mei-gscfi.768-e2c2afa2-3817-4d19-9d95-06b16b588a5d: FW version command failed -5
/var/log/dmesg:[    7.014981] kernel: mei i915.mei-gscfi.768-46e0c1fb-a546-414f-9170-b7f46d57b4ad: Could not read FW version ret = -19
/var/log/dmesg:[    7.014984] kernel: mei i915.mei-gscfi.768-46e0c1fb-a546-414f-9170-b7f46d57b4ad: FW version command failed -5

I am pretty sure this means your system cannot properly initialize the GPU.

Go to my post on page one of this thread and read my Intel Arc Firmware update guide that I linked.