OBS Streaming to YouTube Partial Audio out of Sync

[Church307]

Hello,

I am trying to stream from OBS to YouTube and I am having audio sync issues.

My setup is:
Mics go into a Tascam Mixcast 4. The audio comes out of that into an ATEM Mini Pro. I'm using the USBC out of the ATEM Mini to go to my computer where OBS sees the video through the source Video Capture Device. I can get the audio and video to be in sync on the OBS Video Program window. But once I watch the YouTube Stream the audio happens before the video. If someone claps You hear the clap before you see it.

I have a bumper video that I play on OBS and that audio is lined up on the OBS Video Progam window and when I watch it on YouTube that audio is in sync. I'm not sure why a video I play through OBS lines up perfectly but the footage coming from the ATEM Mini Pro doesn't have the audio lined up. I have been searching on the web for an answer but I can seem to find any answers.

Any help would be greatly appreciated.

 

[AaronD]

I think it's treating the video and audio sources separately, even though they come from the same USB port. It probably has more to do with how the ATEM presents itself to the PC, than it does with OBS handling it.

Anyway, record enough to show the problem, and load that into a video editor. Separate the video and audio into separate tracks in the editor, and play with their alignment until it's right. The circled setting here is that same adjustment in OBS; it's just easier to mess with it in the editor and then translate, than to trial-and-error this one.

 

[Church307]

Thanks for your response!

I have messed with the Sync offset and it doesn't change the delay at all. I'm not sure if I need to do something else. I have also tried adding a video delay (Async) filter to the source. I was able to get that to work on a test last week but once I tried it yesterday on my stream it didn't help at all.

 

[AaronD]

If you've made it something ridiculous and obvious, not just a handful of milliseconds, and it still doesn't change, then you're probably adjusting the wrong source.

There's a checkbox at the bottom left to show Active Sources Only. It's checked by default, which hides everything that is not playing at that exact moment. Uncheck it, and find the actual source that needs adjustment.

For a reasonability check, I have some cameras feeding a 4-input capture card, and a USB stereo line input from an external mixing console. My Sync Offset for that USB stereo line-in is about 310ms. The array of USB video captures that the 4-input card replaced, needed about 500ms. If you can tell which direction it's off, then it's probably at least 100ms; closer than that, just play with it until it feels right.

I don't think you need a video delay. If:

You hear the clap before you see it.

then the audio is early, and that's what needs the delay.

 

[Church307]

If you've made it something ridiculous and obvious, not just a handful of milliseconds, and it still doesn't change, then you're probably adjusting the wrong source.

There's a checkbox at the bottom left to show Active Sources Only. It's checked by default, which hides everything that is not playing at that exact moment. Uncheck it, and find the actual source that needs adjustment.

For a reasonability check, I have some cameras feeding a 4-input capture card, and a USB stereo line input from an external mixing console. My Sync Offset for that USB stereo line-in is about 310ms. The array of USB video captures that the 4-input card replaced, needed about 500ms. If you can tell which direction it's off, then it's probably at least 100ms; closer than that, just play with it until it feels right.

I don't think you need a video delay. If:

then the audio is early, and that's what needs the delay.

Sorry about that I typed it wrong. I see the clap before I hear the audio. It's about a 15sec delay before I hear the clap.

 

[Church307]

OBS preview is exactly synced for both the camera and mic audio and the videos I play. When I watch the stream on youtube the camera and mic audio are out of sync and the video audio is in sync. Why would these be different? The preview looks perfect but the streamed result is out of sync.

 

[Church307]

Sorry for so many replies. I changed my output Video Bitrate from 3500 to 6500 and the audio and video are synced without having to add any delay in the video or audio.

 

[AaronD]

I changed my output Video Bitrate from 3500 to 6500 and the audio and video are synced without having to add any delay in the video or audio.

Okay, *that* is weird. The bitrate shouldn't have made any difference at all, except for clarity. Are you sure that nothing else changed?