USB Capture Device Mono instead of multi-channel

[DurzoBlint123]

Hello. This might be more of a question about the capture device than the software, but I figured I'd start here, since the "manufacturer" of this cheap card seems non-existent.
I bought a cheap USB 3 HDMI capture device from amazon (one of those thumb drive looking ones). And it says on the box that supported audio is "L-PCM" which I believe is multi-channel.
I have OBS set to stereo for audio settings. However, when I select the setting of the audio device and select "USB 3.0 capture device", it only shows 1 channel bar instead of 2. And if I go into windows 10 -> Control Panel -> Sounds -> Recording devices and select the USB 3.0 device, it says it's a "1 channel MIC".
And when trying a recording in OBS anyway, the audio is noticeably low quality.
It didn't come with any drivers and the company doesn't seem to exist on the internet anywhere to ask for support.
Has anyone else here used one of these devices?
It's a shame because the video quality comes in crystal clear. It's just the audio that's garbage.

 

[mullar226]

i've had this same problem too, the only solution i've found myself is to use a linux distribution, i guess pulseaudio is better at detecting sound card channels or whatever, hope this helps.

 

[FerretBomb]

Hello. This might be more of a question about the capture device than the software, but I figured I'd start here, since the "manufacturer" of this cheap card seems non-existent.
I bought a cheap USB 3 HDMI capture device from amazon (one of those thumb drive looking ones). And it says on the box that supported audio is "L-PCM" which I believe is multi-channel.
I have OBS set to stereo for audio settings. However, when I select the setting of the audio device and select "USB 3.0 capture device", it only shows 1 channel bar instead of 2. And if I go into windows 10 -> Control Panel -> Sounds -> Recording devices and select the USB 3.0 device, it says it's a "1 channel MIC".
And when trying a recording in OBS anyway, the audio is noticeably low quality.
It didn't come with any drivers and the company doesn't seem to exist on the internet anywhere to ask for support.
Has anyone else here used one of these devices?
It's a shame because the video quality comes in crystal clear. It's just the audio that's garbage.

L-PCM is "Linear Pulse-Code Modulation", which is a method used to digitally represent sampled analog signals in which the quantization levels are linearly uniform. It's a sampling and encoding type; it doesn't infer number of channels, sample rate available, or compression type (if any).
It may very well actually be a mono-only audio device, especially if it shows up as one in the Windows 'Recording Devices' properties.

This is the problem with buying cheap capture devices, especially no-name Chinesium ones.
They tend to cheap out insanely on a lot of stuff, taking ridiculous shortcuts to save a fraction of a penny to keep production costs down.
Also a lot of them pretend to be USB3, but are actually only using USB2 signaling for data transport as it's much simpler and cheaper to do. So no USB3 bandwidth.

 

[carlmart]

OK, then the problem is in the "cheap" capture device. But I've seen a similar complaint on another forum about an El Gato capture device.

So how can we know which capture device captures audio as it originally is?

On mine, which is a generic Chinese one, the audio passes through the device suffering no HDMI loss. The OBS program on my laptop audio setup shows two input channels. But when I plug in the USB connector shows just one channel.

Perhaps this is made on purpose? Or are there capture devices that do output stereo or 5.1 audio?

 

[Tomasz Góral]

Carlmart which device you have?

 

[carlmart]

Carlmart which device you have?

The device has no brand or model name. It only says HDMI video capture.
I have seen if for sale also in Amazon, and many of the units had no name at all.
Bought it from AliExpress. There other HDMI switches and HDMI audio capture small boxes I bought that always worked fine, so I wouldn't say it's a problem of quality.
My guess is this low priced devices are all very similar, do the video capture fine but mono the audio. I'm starting to see other devices, both with Windows and Mac, that have a similar problem.
What I wonder is if there's some capture box that is guaranteed to capture stereo or multichannel audio.
Perhaps these people that do YouTube demos have any info on that.

 

[Tomasz Góral]

Device descriptor?
You can find in Device Manager.

 

[carlmart]

Something is not right in my OBS installation or setup. I re-installled the program several times, and I don't get the + option in sources. The device is disconnected. What might be happening and what can I do?

 

[carlmart]

It now seems the capture device is dead. No image or audio is showing on OBS screen.
I will try it on my pc before throwing it away.

 

[carlmart]

But now I'm beginning to think if Windows 10 latest upgrade hasn't got anything to do with the device not working anymore.
It wouldn't be the first time.

 

[carlmart]

OK. Some news. I installed the capture device on my desktop PC, using the Shield with Netflix as source to capture.
Voilá! Image is on, but audio isn't, not even mono.
The device shows as "USB video" in Windows "Bluetooth & other devices", and it has no access to internal setup. You can just remove it.
So I wonder if it's possible to get stereo or multichannel from this capture device or not.
Anyone can give me any clues on how to proceed on OBS, if there's anything else I can do for audio setup, which it seems to be wrong somewhere?

 

[pojkrummet]

Anyone can give me any clues on how to proceed on OBS, if there's anything else I can do for audio setup, which it seems to be wrong somewhere?

So, guessing I'm using the same capture card. Had the same problem, the audio from the capture card was super-low and distorted. Did a few hours of tweaking and searching to no betterment. Ended up getting the audio from the TV's headphones-plug and routing it back into OBS studio through an audio interface. Terrible workaround, but it works

 

[rorutokun]

Turns out these cheap capture cards' claim that they audio output is 1 channel 96KHz but the truth is that it's actually two 48KHz channeles squeezed together because of a bug in drivers or whatever.

The solution for that is this program:

GitHub - ToadKing/mono-to-stereo: Convert a mono input stream to a stereo one

Convert a mono input stream to a stereo one. Contribute to ToadKing/mono-to-stereo development by creating an account on GitHub.

github.com

It takes that malformed input and plays it out to the device of your choice with the channels properly split into left and right.

Two things that might come in handy:
- it has a bug where it won't output the audio if your output device doesn't support 16bit 48KHz (mine doesn't ^^') - in this case you can use Voicemeeter (see https://github.com/ToadKing/mono-to-stereo/issues/12)
- you might want the audio to still be a recording device, not played directly into your playback device - in this case, use Virtual Audio Cable (VAC) of your choice

 

[justdanjy]

Turns out these cheap capture cards' claim that they audio output is 1 channel 96KHz but the truth is that it's actually two 48KHz channeles squeezed together because of a bug in drivers or whatever.

The solution for that is this program:

GitHub - ToadKing/mono-to-stereo: Convert a mono input stream to a stereo one

Convert a mono input stream to a stereo one. Contribute to ToadKing/mono-to-stereo development by creating an account on GitHub.

github.com

It takes that malformed input and plays it out to the device of your choice with the channels properly split into left and right.

Two things that might come in handy:
- it has a bug where it won't output the audio if your output device doesn't support 16bit 48KHz (mine doesn't ^^') - in this case you can use Voicemeeter (see https://github.com/ToadKing/mono-to-stereo/issues/12)
- you might want the audio to still be a recording device, not played directly into your playback device - in this case, use Virtual Audio Cable (VAC) of your choice

Thanks for this but I'm not sure how to run this to fix it?
I have one of those cheapy Chinese capture cards and it works perfectly, no lag in OBS and whilst passing through the audio and monitoring it - even with a wireless USB headset.
The only problem is that it's single channel audio so directional game sound is missing which is problematic when playing a game which requires you to hear where sound is coming from.
I downloaded the mono-to-stereo.exe from a different source and ran it but it didn't seem to do anything. The link above takes you to GitHub but how do you actually use it? Sorry for the dense question!

EDIT - OK I think I figured out how to download it but it doesn't appear to be doing anything. I've run the program and no error messages, cmd window opens and shuts within 1 second. The recording device Digital Audio Interface still shows as single channel 96000 Hz.
How do you get this working so it's properly outputting the 2 channels being fed to it?

 

[rorutokun]

Thanks for this but I'm not sure how to run this to fix it?
I have one of those cheapy Chinese capture cards and it works perfectly, no lag in OBS and whilst passing through the audio and monitoring it - even with a wireless USB headset.
The only problem is that it's single channel audio so directional game sound is missing which is problematic when playing a game which requires you to hear where sound is coming from.
I downloaded the mono-to-stereo.exe from a different source and ran it but it didn't seem to do anything. The link above takes you to GitHub but how do you actually use it? Sorry for the dense question!

EDIT - OK I think I figured out how to download it but it doesn't appear to be doing anything. I've run the program and no error messages, cmd window opens and shuts within 1 second. The recording device Digital Audio Interface still shows as single channel 96000 Hz.
How do you get this working so it's properly outputting the 2 channels being fed to it?

Ah, sorry for leaving no explanation on usage, the github page really lacks a manual for people who are not familiar with commandline tools.
So, the easiest way to run it is like this:
0. Go to github, click on Releases on the right, download .zip file for 32bit or 64bit windows (most likely you use 64) and unzip it in some easy to reach place
1. Open the folder containing the mono-to-stereo.exe
2. Click on address bar, type cmd instead of path there and hit enter

3. In the console that opened, type:

.\mono-to-stereo.exe --list-devices

and hit enter. You will see the list of playback ("render endpoints") devices and recording devices ("capture endpoints"):

Audio of your capture card will be among "capture endpoints". There is a high chance that it will be called "Digital Audio Interface (USB Digital Audio)" if you have an english Windows. If you don't it might have a different name - on my screenshot it's "Cyfrowy interfejs audio (USB Digital Audio)".
4. Now, if your capture card has a default english name and all you want to do is to redirect it to your current default playback device, you don't need any additional parameters and you can just run:

.\mono-to-stereo.exe

If this is not the case, copy both the "capture" and "render" devices you want to use and paste them into this command:

.\mono-to-stereo.exe --in-device "CAPTURE CARD AUDIO DEVICE NAME HERE" --out-device "PLAYBACK DEVICE NAME HERE"

and hit enter, you should see something like this:

and nothing more, it should just stay like this (sometimes it may output some additional info which is not important). Do not close this window until you want to stop using the program.

Now, the audio coming from your capture card should be played back through the device you chose. If you chose your default playback device, you will see it in OBS together with all your other system sounds. If you chose a custom audio device which is different from your default playback device or you're not using system's stereo mix in OBS, use "Audio Output Capture" and select the audio device you put into "--out-device" to capture the now-stereo sound ;)

You are no longer supposed to use "Audio Input Capture" to get the audio as it will always be a mono audio.

Hope that helps!

 

[elizois232]

Ah, sorry for leaving no explanation on usage, the github page really lacks a manual for people who are not familiar with commandline tools.
So, the easiest way to run it is like this:
0. Go to github, click on Releases on the right, download .zip file for 32bit or 64bit windows (most likely you use 64) and unzip it in some easy to reach place
1. Open the folder containing the mono-to-stereo.exe
2. Click on address bar, type cmd instead of path there and hit enter
View attachment 90718
3. In the console that opened, type:

.\mono-to-stereo.exe --list-devices

and hit enter. You will see the list of playback ("render endpoints") devices and recording devices ("capture endpoints"):
View attachment 90720
Audio of your capture card will be among "capture endpoints". There is a high chance that it will be called "Digital Audio Interface (USB Digital Audio)" if you have an english Windows. If you don't it might have a different name - on my screenshot it's "Cyfrowy interfejs audio (USB Digital Audio)".
4. Now, if your capture card has a default english name and all you want to do is to redirect it to your current default playback device, you don't need any additional parameters and you can just run:

.\mono-to-stereo.exe

If this is not the case, copy both the "capture" and "render" devices you want to use and paste them into this command:

.\mono-to-stereo.exe --in-device "CAPTURE CARD AUDIO DEVICE NAME HERE" --out-device "PLAYBACK DEVICE NAME HERE"

and hit enter, you should see something like this:
View attachment 90721
and nothing more, it should just stay like this (sometimes it may output some additional info which is not important). Do not close this window until you want to stop using the program.

Now, the audio coming from your capture card should be played back through the device you chose. If you chose your default playback device, you will see it in OBS together with all your other system sounds. If you chose a custom audio device which is different from your default playback device or you're not using system's stereo mix in OBS, use "Audio Output Capture" and select the audio device you put into "--out-device" to capture the now-stereo sound ;)

You are no longer supposed to use "Audio Input Capture" to get the audio as it will always be a mono audio.

Hope that helps!

Yo dude It works, thank you very much for leaving this guide, I have exactly the same issue as the OP. But the capture card I got only uses usb 2.0, thats the only difference, but I also just bought it from wish, so I think this would also work on them, now it works perfectly with my PS5, thank you!!

 

[Helgol]

... ob es eine Capture-Box gibt, die garantiert Stereo- oder Mehrkanal-Audio aufnimmt.

Schau mal bei Hauppauge. Ich habe den HD-PVR mit Toslink Ein+Ausgängen, leider nur mit Component-Videoeingängen. Den gibt es deswegen gebraucht schon sehr günstig. Der PVR2 soll es über HDMI auch können, aber ohne Hilfe des Supports konnte ich es nicht zum Laufen bringen.

 

[Helgol]

Es stellt sich heraus, dass diese billigen Capture-Karten behaupten, dass ihre Audioausgabe 1 Kanal 96KHz ist, aber die Wahrheit ist, dass es tatsächlich zwei 48KHz-Kanäle sind, die wegen eines Fehlers in Treibern oder was auch immer zusammengequetscht werden.

Bei mir hat es mit "mono-zu stereo.exe" nur halb funktioniert. Ich erhalte nämlich Dual-Mono statt Stereo. Sollte es für diese Billigteile auch eine Möglichkeit geben auf 5.1-Multichannel zu patschen, wäre ich euch auf ewig dankbar! Wahrscheinlich muss ich doch das virtuelle Kabel ausprobieren, oder?

 

[swimmerpepe]

Ah, sorry for leaving no explanation on usage, the github page really lacks a manual for people who are not familiar with commandline tools.
So, the easiest way to run it is like this:
0. Go to github, click on Releases on the right, download .zip file for 32bit or 64bit windows (most likely you use 64) and unzip it in some easy to reach place
1. Open the folder containing the mono-to-stereo.exe
2. Click on address bar, type cmd instead of path there and hit enter
View attachment 90718
3. In the console that opened, type:

.\mono-to-stereo.exe --list-devices

and hit enter. You will see the list of playback ("render endpoints") devices and recording devices ("capture endpoints"):
View attachment 90720
Audio of your capture card will be among "capture endpoints". There is a high chance that it will be called "Digital Audio Interface (USB Digital Audio)" if you have an english Windows. If you don't it might have a different name - on my screenshot it's "Cyfrowy interfejs audio (USB Digital Audio)".
4. Now, if your capture card has a default english name and all you want to do is to redirect it to your current default playback device, you don't need any additional parameters and you can just run:

.\mono-to-stereo.exe

If this is not the case, copy both the "capture" and "render" devices you want to use and paste them into this command:

.\mono-to-stereo.exe --in-device "CAPTURE CARD AUDIO DEVICE NAME HERE" --out-device "PLAYBACK DEVICE NAME HERE"

and hit enter, you should see something like this:
View attachment 90721
and nothing more, it should just stay like this (sometimes it may output some additional info which is not important). Do not close this window until you want to stop using the program.

Now, the audio coming from your capture card should be played back through the device you chose. If you chose your default playback device, you will see it in OBS together with all your other system sounds. If you chose a custom audio device which is different from your default playback device or you're not using system's stereo mix in OBS, use "Audio Output Capture" and select the audio device you put into "--out-device" to capture the now-stereo sound ;)

You are no longer supposed to use "Audio Input Capture" to get the audio as it will always be a mono audio.

Hope that helps!

Thanks a lot for this comprehensive guide and steps... bad news for me is that it still doesnt work. The device name is the default as you say and it outputs the audio to my headphones with the same issue than in OBS. Could I be missing something? I am on windows 11 and same on the device settings it appears 1 channel 16 bit 96khz.

 

[rorutokun]

Thanks a lot for this comprehensive guide and steps... bad news for me is that it still doesnt work. The device name is the default as you say and it outputs the audio to my headphones with the same issue than in OBS. Could I be missing something? I am on windows 11 and same on the device settings it appears 1 channel 16 bit 96khz.

Sorry for the late reply. If you're still struggling to solve the issue, could you share a bit more details?
1. Output of ".\mono-to-stereo.exe --list-devices"
2. Command you're running to split the audio (step 4 from my guide) and all the output of it that you see in the console
3. Where is the sound mono instead of stereo? In your headphones? In you OBS? Both?
4. How do you capture the desired sound in OBS? (source type and its settings)