18.1.3 - MP4 AAC LC clips no longer play audio

Upgraded to 18.1.3 and now my MP4 clips with AAC LC audio (from a DJI Action2) no longer has any Audio playback or waveforms in Resolve Studio (Windows 11).

Here is a sample - https://behome.dyndns.info/index.php/s/7xsK2rL92qQATbP

These clips used to be fine, and I opened old projects with similar clips and they too now have no Audio output.

Double checked, and these clips play fine in Windows Media Player as well a Chrome (and JRiver Media Center) so it does not appear to be a "Windows Issue".

In addition, I have the same issue with finished projects that had already been rendered our from Resolve with AAC. While they play in just fine, if I bring them onto a resolve timeline I don't have any audio.

Edit - other clips on the TimeLine play fine (eg MXF)

Still scratching my head. Inspector seems to like them, just no actual audio is played.

aac.jpg (61.87 KiB) Viewed 4020 times

No problem with playing AAC audio in a similar clip on my system. Have you checked your audio settings in Preferences/System/Video and Audio I/O, and also the routing in the Fairlight Patch menu? Maybe a Windows update has changed things.

The sample clip has audio here in Studio 18.1.3 on Windows 10.

I missed your sample clip first time around. Like Jim, it plays fine here too.

Thanks for testing - I've checked my settings and don't see anything wrong (but....). The thing is other non AAC clips play just fine.

Also in checking my prior projects (that worked fine at the time), now also have this issue.

I've created a simple project with two clips on the time line:
- MP4/AAC = No Audio
- MXF = Audio is Fine

Here is a copy of the archive - https://behome.dyndns.info/index.php/s/CMr3Neb2Xx3Lyab

I'm wondering if it is a Win11 Update but..... the next option is to install an earlier version of resolve 18 to check but before I do this I'd like to rule out the Noob setting behind the screen!

Also did some testing remuxing the original MP4 with AAC to:
- MOV with AAC : No Audio in Resolve (but fine in Windows)
- MKV with AAC : No Audio in Resolve (but fine in Windows)
- MKV with PCM : Audio played fine in both Resolve and Windows!

So it still seems that something is up in Resolve with AAC on my setup.

I tried all DR version back to 18.1.x - all the same thing. I did not try back to 18.0.x as the database has a different format.

I'm guessing it is some DR vs Win11 Insider Preview 10.0.22622.290 (installed 7/7/2022). I checked and I've not edited MP4/AAC since that windows update till this week.

I can also confirm it is a AAC Decode Issue Only. I can still create and render a project out as MP4 with AAC and it will play in Windows just fine. If I bring that clip back into DR then there is no audio even though the AAC track is recognised.

[Dwaine Maggart]

Stupid question: are you sure you have Studio installed? If you select the About DaVinci Resolve menu, it says Studio?

Yup 18.1.3 Build 8 Studio

Currently, I've had to pre-convert from MP4/AAC to MKV/PCM

What happens if you re-wrap it into .MOV?

As too an earlier post, just wrapping it in other container (tried MOV and MKV) does not work, same result.

Can you post a short sample on a cloud service to test?

There is both a sample clip from the DJI and a Backup project already linked in this thread (see above posts).

OK, sorry, I didn't see it. Oh, one of the most beautiful buildings in the world. I was visiting there about 40 years ago and it's a lasting memory.

Well, audio is playing here on the Mac I can edit it and, for example, blend it. But something is wrong, since I can't get the waveform displayed, neither in the preview window nor in the timeline.

No probs - I expect it is one for Dwaine!

[Dwaine Maggart]

I'd like to look at your sample clip and/or archive, but when I click your links, I get this:

Your connection is not private
Attackers might be trying to steal your information from behome.dyndns.info (for example, passwords, messages, or credit cards). Learn more
NET::ERR_CERT_AUTHORITY_INVALID

Would it be possible to post the clips in a different location, like Dropbox or Google Drive, or something like that?

The audio is very low but if you up the clip gain you should see this.

I'd like to look at your sample clip and/or archive, but when I click your links, I get this:

Your connection is not private
Attackers might be trying to steal your information from behome.dyndns.info (for example, passwords, messages, or credit cards). Learn more
NET::ERR_CERT_AUTHORITY_INVALID

Would it be possible to post the clips in a different location, like Dropbox or Google Drive, or something like that?

That is weird - I get from my end on the cert

sslcert.png (62.92 KiB) Viewed 3483 times

and the Nextcloud security scan looks good - https://scan.nextcloud.com/results/beea ... 2b0df8486d

Here is a OneDrive link - https://1drv.ms/u/s!AkiTPpgNxBQV5gwJqeO ... n?e=bqZYfM

This is for the Archive that includes the original MP4 Clip.

The audio is very low but if you up the clip gain you should see this.

Unfortunately, not for me. 0 wave form (and audio) at any gain.

Neither here. The audio plays and the volume seems normal, but there are no waveforms.

[Dwaine Maggart]

Both clips in your archive have audio and waveforms on the following for me:

Windows 10 Pro 20H2 desktop system with Resolve 18.1.3 Studio and a GTX 1050Ti GPU.

Windows 11 22H2 laptop with an RTX A4500 GPU and Resolve Studio 18.1.3. The laptop has the latest Win11 22H2 cumulative updates package installed.

Windows 11 22H2 laptop with an RTX3000 GPU and Resolve Studio 18.1.3.

So I'm not sure why it wouldn't be working for you, or why others are not getting waveforms.

Please send links to a Resolve log generated from the Resolve Help menu: Create Diagnostics Log on Desktop, and a Windows System Information .NFO file. Perhaps there will clues in one of those.

I noticed something similar with the GoPro 5 camera, today I was looking for a solution. When I turned off "Voice Isolation" it all came back to normal.

Screenshot 2023-02-08 194643.jpg (7.17 KiB) Viewed 3331 times

Screenshot 2023-02-08 194708.jpg (11.41 KiB) Viewed 3331 times

Both clips in your archive have audio and waveforms on the following for me:

Please send links to a Resolve log generated from the Resolve Help menu: Create Diagnostics Log on Desktop, and a Windows System Information .NFO file. Perhaps there will clues in one of those.

Done, link sent in PM

I noticed something similar with the GoPro 5 camera, today I was looking for a solution. When I turned off "Voice Isolation" it all came back to normal.

Thanks but, it's not VI for me. Don't get sound even in the Bins. Separating out the AAC track on it's own also does not work.

FYI - Been working with Dwaine on this. Tried a bunch of stuff. Rolling back to 18.0.1 works (waiting for feedback Dwaine on what next to try to narrow down what is "special" for me with 18.1.x)

edit:

18.0.1 - No issues
18.0.4 - No issues
18.1.x (all versions) - Issue with no AAC audio

edit 2: Upgraded 18.0.4 to 18.1.3 (database upgraded) and then the issue of no AAC Audio was back.

Fixed with a Nuke and Pave of Windows (also used the opportunity to get the latest i9).

Thanks for all the help and here is hopping I don't need to do another Windows clean install again!

FYI - Been working with Dwaine on this. Tried a bunch of stuff. Rolling back to 18.0.1 works (waiting for feedback Dwaine on what next to try to narrow down what is "special" for me with 18.1.x)

edit:

18.0.1 - No issues
18.0.4 - No issues
18.1.x (all versions) - Issue with no AAC audio

edit 2: Upgraded 18.0.4 to 18.1.3 (database upgraded) and then the issue of no AAC Audio was back.

Both clips in your archive have audio and waveforms on the following for me:

Windows 10 Pro 20H2 desktop system with Resolve 18.1.3 Studio and a GTX 1050Ti GPU.

Windows 11 22H2 laptop with an RTX A4500 GPU and Resolve Studio 18.1.3. The laptop has the latest Win11 22H2 cumulative updates package installed.

Windows 11 22H2 laptop with an RTX3000 GPU and Resolve Studio 18.1.3.

So I'm not sure why it wouldn't be working for you, or why others are not getting waveforms.

Please send links to a Resolve log generated from the Resolve Help menu: Create Diagnostics Log on Desktop, and a Windows System Information .NFO file. Perhaps there will clues in one of those.

I have a similar problem here viewtopic.php?f=38&t=183433#p960040

@Dwaine Have you find any idea what could cause this or what could I try? This is a brand new two days old system, so wouldn't want to start reinstalling windows.

Thank you for any help!

Looks like this problem fixed itself with running all windows updates! Should have checked those earlier. I can hear the sound now and the bars are moving in the mixer. Waveforms are also working when I import the clips to a new project.

Thank you all!

I'm using DaVinci Resolve Studio 18.6 with Linux Mint and the same issue applies here. Last month it manifested with OBS. OBS insists on using AAC as the audio codec. I decided to try upgrading OBS and the update included a second option for audio codecs which is Opus. As soon as I began using Opus instead of AAC, DaVinci Resolve Studio began showing an actual waveform for the audio portion of the video. Prior to this change the green waveform would be just a flatline even though I could play the same MP4 video in other applications on the same machine. Today it has manifested again with videos downloaded from FaceBook. The audio codec for the video is AAC. And I can play the video on my Linux machine in 3 separate apps simultaneously with staggered timing and there's definitely audio. Yet when I select any of these videos from a Bin and place it on the timeline, the associated waveform is flat. And it cannot be amplified because Resolve Studio acts like the track is present but silent. I'm saying there is visual confirmation that the software is not showing a waveform. And so I'm having to use Handbrake or FFMPEG to re-encode the videos so that DaVinci Resolve Studio will recognize it. I assure you that I am using the Studio version of the software. It is not a Linux system problem with sound. You can probably guess how I feel about Macintosh Hardware and Operating Systems from Microsoft so no point in asking me to find one of those machines for testing. I gladly paid for the Studio version in awe-struck gratitude towards BlackMagic for allowing me to escape the tyranny of Apple and Windows. The software really milks the video engine in my RTX 4070 and that helps me get the most out of my investment. It's too bad it doesn't like AAC audio tracks anymore.

I'm having a problem getting DaVinci Resolve Studio to interpret the AAC audio portion of any video clip I import. While DaVinci does acknowledge that the audio track is there, and while it can give me information regarding the number of channels present in the video clip, it cannot show the waveform for the video clip or play back the audio associated with it. So at the Edit page I will see the thumbnails for the video portion while the audio track is a nice green, yet flat line with no waveform. Meanwhile, I can open the same clip in 3 or 4 applications at the same time and let them all play. This would include OpenShot, HandBrake, VLC, Smplayer, Totem, OcenAudio, etc. And now regarding the clip itself. Well it could be an MP4 with AAC audio that came from my smart phone. Or it could be a DVD backed up with Handbrake. Or it could be a YouTube video downloaded with yt-dlp. Or it could be a video downloaded from FaceBook using Fdown.net. Or it could be stock footage from Pexels. Or it could be something I recorded using OBS and AAC audio encoding. Somehow - DaVinci Resolve Studio is doing something different when it reads the file. Different from every other piece of software on my machine. I spent hours re-encoding video clips in various formats to troubleshoot the problem. So I tried an MKV container with opus. Or an MKV with vorbis. With OBS, DaVinci Resolve Studio is only able to intepret the audio (that means, show me the audio and also play it back) when I switch to Opus encoding instead of AAC. With MP4 clips, if I use Handbrake to add another audio track that is either Opus or pcm_s16le - DaVinci Resolve Studio is magically able to reproduce the audio. I'm using Linux Mint 20. At the moment I'm running DaVinci Resolve Studio 18.6.5 and I can downgrade as far as 18.5

Well this is happening on two of my machines and the problem is purely with the AAC stream. At first I thought it was related to MP4 files. But I can take an MP3 and export it as an M4A or an AAC or a DTS file - all 3 can contain an AAC encoded stream. Resolve Studio wouldn't import the DTS or the AAC. As for the M4A it doesn't show the waveform. You can play it, but it is silent. I can play these same files in Firefox, Chromium, Foobar, VLC, and Openshot - but DaVinci Resolve Studio 18.6.5 doesn't know how to interpret the stream. It only acknowledges Flac, Opus, Vorbis, and PCM. And this is bad news for me because every video clip that I receive has an AAC stream for the audio portion. When I import any video file with AAC audio, the audio track is a flatline. All of my machines run Linux. Feel free to post a link to any piece of media you choose - so long as the audio portion is AAC. I'll be happy to download it and then post screenshots or perhaps a video of how Resolve Studio interprets it.

[Dwaine Maggart]

Not a surprise since Linux Resolve does not support AAC audio. I don't expect that to change anytime soon, if ever.

As noted in the supported codecs doc:

https://documents.blackmagicdesign.com/ ... 5996810000

Thank you Dwaine. Your answer is clear and it addresses the situation. I was unaware of that limitation. It is definitely reflected in the document that your link points to.

And yet, this might be a great opportunity to provide some additional information regarding the stance that Blackmagic has taken with regard to this matter.

Do you find that Blackmagic encountered some insurmountable technical challenge with interpreting AAC audio streams within Linux? Or perhaps a licensing issue?

I'm in "listening mode" here and not "judging mode". And by that I mean I'm not trying to start a debate or an argument. It's just that I did buy the Studio version if that means anything. And I was really looking forward to thumbing my nose at some of the people in my life who are die-hard Final Cut Pro and Adobe Premiere people. Not because I think less of them. But because I am able to "do my own thing."

Thank you for your time. And I look forward to your reply.

I have a similar issue.

On my Studio 18.6.6 on Windows 11, MP4 video with audio...

AAC LC SBR (Implicit) (HE-AAC):
Video plays choppy in the Media bin, but it plays smooth in the timeline.
Audio shows no waveform, no audio playback.

After re-encorded by HandBrake using AAC(avcodec), it's converted to....

AAC LC:
Video plays smooth in everywhere.
Audio shows waveform, with audio playback.

I checked these info above with MediaInfo.

[Dwaine Maggart]

Please provide a link to the file.

Please provide a link to the file.

https://1drv.ms/f/s!AjKlvzn25scoz2Tmn6P88Zna6U0A

The video named choppy is a random YouTube music video downloaded and converted to mp4 by TubeDigger.
The smooth one was re-encorded by HandBrake.
VLC plays both files with no problem.

[Dwaine Maggart]

Thanks for the files. I see the issue as well on Windows. Both files are good on Mac. It appears that the AAC LC SBR audio codec is the issue. I've reported to the dev team.

This is just a suggestion but, how about displaying detail of codecs in the metadata pane?
Both files are displayed as "AAC" and not "AAC LC", nor "AAC LC SBC".
I needed to open the files in the MediaInfo to see the codecs.
Maybe this type of issue could be sorted out quicker with the info.