How to Record Multiple Audio Tracks in OBS with Uncompressed Audio?

[drodi]

Hey guys,

I’ve got an issue with OBS when trying to record a video with multiple audio tracks. My setup is pretty straightforward: I have three different audio sources, one from my DAW, one from my mic, and another from game+Chrome audio. My goal is to record these three audio sources on separate tracks so I can edit them independently in post, like adjusting gain, fixing clipping, and so on.

Now, I’ve followed the standard tutorials online about recording multiple audio tracks in OBS. The general idea is to:

1. Use the MKV format for output.
2. Remux the MKV to MP4 afterward.
3. Drag and drop the MP4 into a video editor, where the audio layers are separated based on the tracks I set up in OBS.

This works fine if set the audio encoder in the Recording tab to "Use Stream Encoder." However, here’s where my problem starts:

If I switch the audio encoder to FFmpeg 32-bit Float to record the audio tracks as uncompressed, this workflow stops working. The video file gets generated, but instead of having separate audio tracks, it only contains a single audio layer. This is a big issue because I want my audio tracks recorded in an uncompressed format, not lossy streaming audio.

So, my question is: Is there a way to record multiple audio tracks in OBS with uncompressed audio, without being forced to use the lossy "Use Stream Encoder" option?

It’s frustrating because this limitation kind of forces you to stick to lossy audio, which defeats the purpose of having clean audio tracks to work with in post. Am I missing something here, or is this just how OBS handles multi-track recording?

Would love you guys tell me if There is a fix to this , it will help a tone

 

[koala]

Works for me. Are you sure your video editor supports this?

I set OBS to create 6 audio tracks ffmpeg pcm 32-bit float format, then created a *.mp4 in hybrid mode with OBS - contains 6 tracks (this is a safe alternative to record to *.mkv+remux to mp4)
I also created a *.mkv - contains 6 audio tracks. With automatic remuxing it also created a *.mp4, which also contains 6 audio tracks.
Verified with MediaInfo. Check your video with MediaInfo (or ffprobe) to determine if it's an issue with your video editor.

This is the auto-remuxed mp4:

 

[drodi]

Hi @koala, Thanks for pointing that out. I’ve verified it, and you’re correct ,the MP4 file does contain the different PCM audio layers. but, for some reason, when loaded into a timeline in editing software, it’s unable to load the other audio layers (beyond the first one). btw, This issue only occurs when the MP4 file contains multiple PCM or FLAC audio layers, it only displays the first audio layer. However, if the MP4 contains multiple AAC or streaming codec layers, it can load them without any problem.

Since you brought this up, I tested it in Davinci Resolve, and it loads the audio layers normally in the timeline. So, the issue is definitely with Premiere Pro, not OBS.
I’ll contact Adobe and see what they can do about it. For now, I think I have two options:

1. Extract the audio layers (uncompressed export) from the MKV files using Audacity or some custom python script, then load the extracted audio files alongside the MP4 in Premiere Pro and work as usual.
2. Work with Davinci Resolve instead.

In either case, this is not an OBS issue, it’s clearly an issue in premiere pro ability to handle multi-audio PCM from MP4 files. ( btw, even Audacity is unable to load the multi-audio PCM from MP4 , when i mentioned loading through audacity, I was able to load them throught the .mkv but when trying with MP4 i got this type of error "an Advanced Audio Coding file. Without the optional FFmpeg library, Audacity cannot open this type of file. Otherwise, you need to convert it to a supported audio format, such as WAV or AIFF." .... Although I have already installed the FFmpeg packages for audacity, which is how i was able to exract the multiple audio from the mkv.)