Mute second monitor

[Droffar]

Hello, I'm having trouble. How to mute one monitor in dual setup? I have a stream on one screen and would like to listen to something on the other. Unfortunately, I can't separate the two and the other screen is audible on the stream.

how should I set the sources or sound mixer to make it work, thank you in advance

 

[AaronD]

It has nothing to do with screens. Look at sources instead. Specifically:

Monitor feeds your headphones or speakers. Output feeds the Tracks selection here, and then you choose which track(s) to stream and/or record:

If you're in Simple Mode, I believe you're stuck with streaming Track 1 with no way to change that.

Now, if you have Desktop Audio, or an Audio Output Capture in a scene, that is set to the same device as the Monitor (either specifically as shown here, or both Default, or one of each if Default just happens to point to that device):

then that source will also pick up the Monitor. This has nothing to do with OBS, but with the operating system. The point that OBS has access to, to grab a device's output, is *after* everything is combined to feed that output. And so it includes *everything*, including what OBS sent to it. OBS is not copying it; it's just an artifact of how the OS itself processes audio.

Thus, if you want to, for example, capture a game's audio in isolation, and ignore the other stuff going on, then you need to be a little bit more intentional and verbose about how you explicitly design your audio rig. You can't just slap some common settings on and expect it to "just work," but you'll have to work around the limitations of what you're using. And a big source of those limitations is the operating system, not just OBS.

 

[AaronD]

There are some attempts to capture audio directly from a specific app, and some of those attempts come natively with OBS, but I've never seen one work *reliably*. The older "entire device" captures are practically bulletproof, and so I still recommend sticking with those...unless you want to be a long-term beta tester with no guarantee of functionality.

Thus, everything that you want to isolate, must connect to its own dedicated device, which means that you need multiple devices with different apps connected to each one. Those devices can be either physical or virtual, but they must have separate entries in the list of available sound cards. Connect just one app (a game, for example) to one of them, point OBS's Desktop or Audio Output Capture to the same one, *then use a different one for OBS's Monitor* to feed your headphones, and you should be all set.

Except for the additional latency (delay) of a second trip through the operating system's audio handler:
Game -> Device 1 -> OBS Capture and Monitor -> Device 2 -> Headphones
If you can't handle the extra delay, then you probably need all of those dedicated sound devices to be physical, and then wire them to an external mixer that then feeds your headphones. As before, OBS captures one of those devices, and sends its Monitor to another, except that now you *don't* Monitor that capture in OBS.