No AC3 codec in Windows 11 24H2 - Solution is needed

[Averdahl]

If i do a clean install of Windows 11 24H2 i cannot playback mp4 files with 5.1 audio. Microsoft writes "Beginning with Windows 11, version 24H2, the AC-3 codec is no longer included with Windows." and no solution is available such as "Buy the AC3 codec in MS Store now!!".

To reporduce:

1. Do a clean install of Windows 11

2. Install Premiere Pro

3. Import a mp4 file with 5.1 audio.

Result:

The file will be imported as video-only.

Expected result:

That the file imports as Video/Audio and that i can playback the file and hear the 5.1 audio.

Additional info:

If you have upgraded from a prior version of Windows 11 to 24H2 the AC3 codec is included, so doing a clean install of Win 11 24H2 is vital to reproduce this.

I have a HP Z4 G5 workstation and none of the audio drivers for this machine do contain any AC3 codec that Premiere Pro can use.

Any solution from Adobe?

Microsoft document: Codecs in Media Player - Microsoft Support

[Ann Bens]

I dont have mp4 with 5.1 audio but mts files with ac3 5.1 which play fine in the beta.

ac3 stereo works just fine either.

If I set the Preferences to Use File I get 6 mono tracks.

I have media player, vlc and pot player installed.This is indeed an upgrade from an older W11 version

I will check my laptop

https://www.free-codecs.com/download/ac3_filter.htm

We used to do this a long time ago or copy the ac3 codec from Encore?

[Averdahl]

How did you get Win 11 24H2, did you upgrade from let´s say 23H2 to 24H2 or did you wipe the disk and did a fresh install of 24H2? I saw now that you did an upgrade and that explain why it works for you.

[Ann Bens]

Or this one: http://www.vlccodec.com/

Just checked its an upgrade from 23H2

I will check my laptop which is a clean install. (needs charging first.)

[Averdahl]

I ended up using AnWave earlier today. This installed the MS Dolby Digital Atmos Pack but then i noticed an old issue with Premiere Pro, that the files play back out of sync.

VLC, PotPlayer, ShutterEncoder, Pegasys Authoring Works 7 and Pegasys Video Mastering Works 7 play back the same files in perfect sync, even without any AC3 add-ons installed. All Adobe apps play back the files out of sync.

Will try your links tomorrow. 🙂

[Averdahl]

In the end i ditched https://www.free-codecs.com/download/ac3_filter.htm because it wanted to install a trojan. I could not find anything here http://www.vlccodec.com that is a AC3 codec. AnWave worked but requires a download evertime, and Windows Media Player still complained about the lack of Dolby codec.

The best so far that gave med audio in Premiere Pro and audio in Windows Media Player that requires one download only was Download Dolby AC-3/AC-4 Installer - MajorGeeks  that gave me Dolby Digital Plus Decoder for PC OEMs. Both packages are saved on my computer till next time...

It would be great if Adobe fixed this so we can just install Premiere Pro and edit away without issues. No Dolby codecs can be found in Microsoft Store.

[MyerPj]

It's sounding alot like the Dolby audio problem from some years ago...

[MyerPj]

Upvoted, this could cause a real problem going forward.

[Averdahl]

Yes, i think this can be a problem as well and the solution needs to be provided by Adobe. Download install files from odd sites and installers that makes Windows throw warning messages during install is not the way to solve it 2024.

[Richard M Knight]

It seems Windows 11 is dropping the Dolby Digital AC3 codec, does that mean the Premiere will not play videos with that audio?

[Ann Bens]

Just pulled a m2ts with ac3 audio from a Bd and it plays just fine in the beta.

Been running W11 for some time now without issues.

[RjL190365]

It will be dropped beginning with the next major feature update to Windows 11 (24H2). However, this affects only users who reinstall Windows 11 with the 24H2 installer using a clean install. Windows 11 users who upgrade to 24H2 from an older feature update of Windows 11 (such as the current 23H2 version) will still have the AC3 codec installed from that version of Windows.

And yes, Premiere Pro relies solely on that Windows AC3 codec. So, if you perform a clean install of the upcoming 24H2 feature update and then you install Premiere Pro, then your videos with AC3 audio will import without audio.

[MyerPj]

I don't understand what Dolby is doing? Any idea. First it was out of PP, and now out of Windows? What will be the work around?

[John T Smith]

I don't use ac3 but if I did I would go to google and enter

dolby ac3 licensing

To find out... since my GUESS is that dolby wants to sell individual licenses

[RjL190365]

It's not the first time that Microsoft has ended official support for a multimedia codec. Newer versions of Windows no longer include MPEG1 or MPEG2 video support out of the box, making those codecs an optional download instead.

[MyerPj]

That's the only thing I can come up with also.

?

[Ann Bens]

Guessing, you can install an ac3 codec yourself.

[wxthings]

This sounds like the cause of the problem I'm having with no audio on AVCHD .MTS files in Premiere, After Effects and Media Encoder, given that I purchased a brand new workstation with Win 11 installed. https://community.adobe.com/t5/premiere-pro-bugs/video-importing-with-out-of-sync-audio/idc-p/149623...

[Averdahl]

@wxthings

I eventually found Download Dolby AC-3/AC-4 Installer - MajorGeeks and installed the two codecs, AC-3 and AC-4. This is the Dolby Digital Plus Decoder for PC OEMs and that gave me audio in Premiere Pro and audio in Windows Media Player. This is the only decoder that gave me both.

Un-zip the file you download and install the two packages. 🙂

Try that to see if it solves your issue and report back.

[wxthings]

Thanks, but no solution. I installed the AC 3 codec (and reinstalled Premiere 25). While it does bring back the missing audio from the .mts clips, the audio leads the video by about 20 frames in my existing Premiere projects and new Premiere projects (as well as in After Effects compositions.

[wxthings]

I forgot to add that after adding this Dolby decoder on this same new Win 11 24H2 computer, .mts clips do properly have synced video and audio.

[wxthings]

Double sorry... that is after adding this Dolby decoder on this same new Win 11 24H2 computer, .mts clips do properly have synced video and audio in Premiere 23.6.8. but not Premiere 25

[Averdahl]

@wxthings I downloaded Pr 23.6.8 as well and everything works as expected there here as well. I thought that i could trick Pr 25.0 to work if i copied the correct importer from 23.6.8 to 25.0 but noticed that Adobe seems to have changed/renamed those in 25.0 so it was not doable. Thats probably the issue here, that the new importer in Pr 25.0 has a bug that causes those audio issues.

I downloaded the beta as well but the same out-of-sync issue is present there as well.

Do your mts-files have stereo audio or 5.1/surround audio?

I found a "solution" in Pr 25.0:

I used Shutter Encoder and used the Extract feature to extract the audio. If i import that file (.ac3) into Pr 25.0 it is in sync with the video, but it creates a lot of extra job. Pr 25.0 seems to have issues when the video and audio is "baked" in the same file such as mp4 and mts.

For my project i am back in Pr 23.6.8. Thanks for the tip @wxthings 🙂

Double sorry... that is after adding this Dolby decoder on this same new Win 11 24H2 computer, .mts clips do properly have synced video and audio in Premiere 23.6.8. but not Premiere 25

By @wxthings

[wxthings]

Thanks for the insight. My .mts files are stereo audio. I understand the patch/workaround, and I could also transcode/convert my .mts files on a backup computer, but I definitely need a workflow where I don't have to do anything to them.

[Averdahl]

I totally agree! For now the only way seems to be using Pr 23.6.8. Not great but it works unless one need some feature that only can be found in Pr 25.0.

Thanks for the insight. My .mts files are stereo audio. I understand the patch/workaround, and I could also transcode/convert my .mts files on a backup computer, but I definitely need a workflow where I don't have to do anything to them.

By @wxthings