OBS to Zoom, any clean approaches?

[brad_p]

I'm trying to find a clean OBS to Zoom solution. For us, the video is easy, but the audio is hard, and syncing audio with video is a mess. I'm curious what other people are doing out there.

The use case I'm trying to solve: we need to use both OBS to Youtube and OBS to Zoom, We have some remote members who can't use one broadcast tool, so they need a backup tool. Sometimes it's lack of tech ability, sometimes their device just won't install an app, and sometimes they're at a place like a hospital where the firewall blocks it. So we just want to run both options.

What we're currently doing:

Virtual camera + Monitor audio

• Turn on OBS virtual camera, then use that virtual camera in Zoom.
• Install a virtual audio driver, like VoiceMeeter or VB Audio.
• For all OBS audio sources, set in advanced properties to monitor and output. Configure OBS so that all monitored audio goes to the virtual line
• Set Zoom to play the virtual audio line (with original audio on)

But there are three downsides, namely:

• Audio monitor doesn't respect any audio OBS delays you enter, so you can't sync audio with video if needed. But you can add audio delays with VoiceMeeter.
• Audio monitor has a knack for crackling in OBS which I haven't solved
• Audio monitor sometimes needs to be manually set each time, for example prior to a meeting we play an mp3 of prelude music, and audio monitor won't automatically monitor the mp3's audio unless I manually reselect it.

Other ideas I've tried:

NDI

• Install a plugin into OBS which lets you have an NDI output (YouTube videos galore on how to set this up)
• Configure the NDI's tools on the laptop.
• Set Zoom to listen to use the NDI video and audio.

Downsides are:

• Adio/video syncing is a mess. If you adjust it correctly for NDI, then it's off in OBS to YouTube.. If you adjust it correctly for OBS to YouTube, then it's off in Zoom.
• The OBS NDI plugin has a knack for drifting sync as the meeting progresses. If you hit the sync dead on at first, by the end of the meeting you could be several seconds off.
• NDI really ramps up the CPU usage and makes the laptop fan much louder. One laptop couldn't handle it and we had to disable the anti-virus and every other program we could find so our video wasn't choppy.

Custom audio monitor + virtual webcam
This is similar to using OBS's audio monitor tool, but using a plugin that gives more options. The problem here is that the audio is now off-sync by hundreds, if not thousands of milliseconds, and syncing that back with Zoom video is a pain.

So I'm curious for you OBS users, what are all of you doing here? Do you like your approach?

[russellhltn]

I only get part of that, but I think my approach would be to get the audio into the HDMI video stream as soon as possible. Perhaps even putting it into the camera. That way, downstream processes would be handing both together rather than having them take separate routes which invite sync problems.

[Mikerowaved]

NDI really ramps up the CPU usage and makes the laptop fan much louder. One laptop couldn't handle it and we had to disable the anti-virus and every other program we could find so our video wasn't choppy.

First of all, I really appreciate the way you asked your question(s). You laid out what you tried and pros and cons of each setup.

Having quite a bit of experience webcasting, I know that audio sync issues can be a real pain. Everything in the audio and video paths need to be scrutinized for delay. One thing I found is your PC running OBS, Zoom, or whatever, needs to be seriously beefy. Try borrowing a late model notebook with something like a 9th gen i5 or later and see if this improves your sync issues. I try to keep the CPU below 50% utilization, if possible, with 25% or lower being ideal. You shouldn't have to stop other processes to get it to work.

[brad_p]

Thanks for the reply. Unfortunately audio and video for me are separate from the start.

My audio comes from the pulpit. My video comes from a USB camera. I mix them together in the laptop via OBS. USB cameras usually add a small delay, like 50-150 ms from audio, which is definitely distracting when people start talking. So I've got to manually sync them back up.

I could tap into the camera's HDMI out and use that over USB out. But then I'd need a zero latency HDMI to USB converter, and they're usually about $150. But that solution could fix most of my issues as I wouldn't need to manually sync in OBS anymore....

[Mikerowaved]

But then I'd need a zero latency HDMI to USB converter...

Just a heads-up regarding capture devices claiming to have "zero latency". Many have an HDMI input with a pass-through HDMI output, along with the USB output. Their claim of zero latency is usually for the HDMI pass-through path. I don't know of any that give you latency figures for the HDMI to USB path, but it's definitely going to be greater than zero.

With that said, HDMI to USB capture devices are getting better and cheaper all the time. Some only lose a couple of frames, but you have to do your research to find them.

[Wattsuk]

What camera are you using?

Also, what audio capture device are you using? Or are you using in built motherboard soundcard?

[brad_p]

What camera are you using?

Also, what audio capture device are you using? Or are you using in built motherboard soundcard?

Video:
For two chapels, I'm using a FoMaKo 20x PTZ camera. One chapel is using a Sony camcorder.

The FoMaKo cameras have either USB out or HDMI out. I chose the USB out for simplicity as it can go straight into the laptop. It's video is about 100 ms slow, so I offset the audio by 100 ms.

The Sony Camcorder uses an HDMI out, which I then use one of those cheap $15 HDMI to USB converters (you find dozens of manufacturers of these on Amazon). It's video is about 150 ms slow, so I offset audio by 150 ms.

If I could get that camera delay down under 50ms, my issues can go away. But that requires buying a better HDMI capture card, with its own cords and box, and setting it up and down each week. I've learned the hard way the more equipment you have the more chances for errors. Our setup is 100% mobile. So I'd prefer to avoid one more box with cords if I can.

Audio:

All three buildings use a wireless audio transmitter. Long story short, we pull from the pulpit directly, then feed into a laptop as a 3.5mm mic in. It works great.

All three buildings also use a USB condensor mic for hymns and musical numbers, as the pulpit mic is directional and unsuitable for hymns. Sometimes if there is a singer and a piano player, we mix both mics in OBS.

Other:

We play a looped mp3 of prelude music before the meeting starts. We also have OBS scenes which disable camera/mics during sacrament, and also disable mics during the meeting conclusions.

My dream

Zoom and OBS weren't meant to play together. Everyone's solution involves some kind of virtual camera (either NDI or OBS) and have Zoom use that virtual camera. But there isn't a quality equivalent virtual audio line solution, that's the tricky part. My dream is being able to have OBS output into a virtual camera and a dependable virtual audio line. Then Zoom is easy.