Question / Help Audio synced on video recording, but then desynced on stream

[bearsafe]

My blue yeti and C920 has a delay so I recorded myself clapping and applied a 450ms delay. Then when I went to stream I checked out of curiosity and the delay had increased to 900ms so I changed it.

My viewers told me that the audio was desynced and removing the 900ms delay fixed this.

Does anyone know if there is a known issue in delays? It seems that this difference between my mic and webcam can range from 250-1000ms. As this is dynamic I don’t know how to account for it in the static menu option of setting a delay.

Will post a log ASAP. The C920 has all the bells and whistles settings turned off already.

 

[bearsafe]

Just as a brief update, after syncing yesterday, there is now a 300ms gap. I'm so baffled by this incredibly basic task.

https://obsproject.com/logs/vQ2oFHjLb_ghoYuF

 

[bearsafe]

My audio has gone out of sync again after being perfectly adjusted yesterday. Please can someone provide help on this matter?

 

[STEPHANVS]

I can also testify on this matter, however we keep the audio sync on the stream, then fix the recording later...

 

[Daniel Bramblett]

If I understand this problem and the discussion correctly I'm seeing a similar issue and am searching for a solution. In my case the stream audio/video is in synch but the recording is not. The video is about 800ms behind the audio in the recording. Very frustrating. The only reason I'm calling this out is to heighten awareness that others are experiencing similar issues.

 

[bearsafe]

So here we sit with a problem affecting 4 people - anyone that can provide any assistance please?

 

[Zidakuh]

Maybe going into the properties of your audiodevice in the OBS mixer and ticking/unticking the "use device timestamps" (whatever it says, make it the opposite) can help?

 

[bearsafe]

Maybe going into the properties of your audiodevice in the OBS mixer and ticking/unticking the "use device timestamps" (whatever it says, make it the opposite) can help?

Thank you Zidukah for your assistance. I am afraid this does not fix the problem for me.

I note a previous user having the same issue https://obsproject.com/forum/threads/drifting-audio-sync-c920-and-blue-yeti.65950/

If the goalposts did not move on this problem then it would be fine, however it seems that my delay is dynamic. I'm wondering if this is a hardware problem such as USB. I have all updated drivers however.

 

[Zidakuh]

Since I used to have a similar setup (C922, Blue Yeti), but never had this issue, I can't really say TBH.

I would try to replicate the problem, but well..

In any case, I wish you luck in finding a solution.

 

[bearsafe]

Since I used to have a similar setup (C922, Blue Yeti), but never had this issue, I can't really say TBH.

I would try to replicate the problem, but well..

In any case, I wish you luck in finding a solution.

Might I ask how you set up your mic and webcam? Is it similar to: webcam as video capture device, mute the audio, Yeti as an audio input device? E.g, what I'm getting at is not using the Yeti as a custom audio device on the C922?

 

[bearsafe]

Other posters, I've had some assistance from a previous post found via google on this forum with the help of @Fenrir

1. Unplug all of your USB devices
2. Only reconnect essential devices
3. Change webcam resolution to the lowest possible to fill your cam area
4. Ensure your devices that require the higher bandwidth are in the correct USB slots, for example my Biostar mini-itx has 3 different speeds. The quickest of which my Elgato is plugged into.
5. If you have a USB hub, get rid of it. This is applied knowledge from @Fenrir wisdom that USB bandwidth is affected by number of plugged in devices. If you have a 4 USB hub, then I'm going to assume this essentially divides total bandwidth by 4?

After above steps my delay has gone from 200ms+ to 80ms. Now to test this over time to see if the goalposts move again.

@Zidakuh - I have turned off all auto features for my C920, but when OBS restarts they've returned. I'm assuming OBS is pulling these settings from somewhere? Have you had this issue?

 

[Zidakuh]

The C920/C922 resets it's settings every time you reboot. It can somewhat be held in check if using the new LogiTech G-hub. However, some things has to be changed every time you reboot.

As for how I used to have my setup:
C922 as video capture device, audio off in the mixer.
Blue Yeti as audio device, run through VoiceMeeter at 44.1kHz with a 256 sample buffer.

Device timestamps was left at default at the time, only had to tinker with that after moving to a dual-pc setup.

 

[bearsafe]

The C920/C922 resets it's settings every time you reboot. It can somewhat be held in check if using the new LogiTech G-hub. However, some things has to be changed every time you reboot.

As for how I used to have my setup:
C922 as video capture device, audio off in the mixer.
Blue Yeti as audio device, run through VoiceMeeter at 44.1kHz with a 256 sample buffer.

Device timestamps was left at default at the time, only had to tinker with that after moving to a dual-pc setup.

That’s excellent, I will try the new Logitech software.

Out of interest why do you use voicemeeter?

Thanks for your help, would like to check out your stream.

 

[Zidakuh]

It makes routing audio easier for me, also it enables me to use VSThost directly on the mic-in channel. Though I run a DBX 286 preamp now, so I don't need that capability anymore.

Second reason is custom sample buffer, which controls how much latency there is going in and out, and with a low enough buffer, you can even monitor your mic directly from voicemeeter itself.

 

[STEPHANVS]

I'm using rtsp sources with a sq5 mixer via USB (96khz only, and OBS does not recognize the signal... so VB-Audio VoiceMeeter Banana is used as a bridge). Use device timestamps is not checked, audio device delay is set to 450ms delay because of the IP camera's video processing delays.

What I noticed is that if stream is started first and recording second, there is ~ 400ms audio delay in the recording, audio is in sync on the live stream. If recording is started first, then stream is started, audio is OK on the recording, and 400ms delay is present on the stream audio.

 

[Daniel Bramblett]

If I understand this problem and the discussion correctly I'm seeing a similar issue and am searching for a solution. In my case the stream audio/video is in synch but the recording is not. The video is about 800ms behind the audio in the recording. Very frustrating. The only reason I'm calling this out is to heighten awareness that others are experiencing similar issues.

So by chance I found a solution for the local recording audio out of synch issue I was facing. If you select the option to automatically start recording when streaming is started then the out of synch issue manifests in the local recording. If you choose to start streaming and local recording separately then the audio is in synch. Providing you wait a few seconds between when the stream is started and the local recording is started. That's how, by complete chance, I found a solution to the audio synch issue on the recordings I was facing. I hope this helps someone else.

 

[Wally44]

I've not found that this helps. I can create a test that is in sync, but the next time I run the same configuration and procedure it is out of sync. I'm guessing that the beginning of the video feed is somehow random and not consistent. I don't see anyway to fix this.