How do I capture quietly or mute the preview?

[zabadoh]

I want to capture an hour-long video, but I don't want to listen to it while I'm capturing.

I don't see a way to mute the preview.

If I right click the video capture device, and open the Properties popup, I can scroll down to the bottom and change the Audio Output Mode to Capture Audio Only, the sound goes mute, but then the resulting capture is muted too.

Turning off the sound on my PC works, but is there a way inside OBC to accomplish this so I can use my PC while it's capping both audio and video?

 

[FerretBomb]

There is not. OBS is meant to be a live production tool, not a content ripper.
We cannot condone or assist in pirating content, as it sounds like you are intending.

 

[zabadoh]

I object to your baseless accusation of piracy.

 

[zabadoh]

I found the solution, but it might only work for the particular video capture device I'm using, a Hauppauge USB-Live2:

1) Under Sources, right click on the video capture device, and from the right-click menu, open its Properties dialog
2) At the bottom of the Properties dialog, scroll down until you reach the Audio Output Mode, check the box "Use custom audio device"
3) Another pull down selection should appear. In the USB Live 2's case, I was able to select "Hauppauge Cx23100 Audio Capture"

What this did was allow OBS to capture both video and audio from the USB capture device while I could continue using my PC, play other videos and watch YouTube that did not interfere with the captured video and audio.

There were some caveats though:

a) You have to do this before you start capturing, and then you can't turn the preview sound on and off during the capture to check how things are going.
b) This solution did not work for my older, similar looking USB video capture device, a BYTECC VR-203 USB AV GRABBER, which is really flaky anyway, because there was not an entry in the custom audio device pulldown for it.