Question / Help Audio/Video delay sync problems on Facebook Live

[Vincent.]

Hello,

So I've been having problems syncing audio with video through OBS. We're streaming on Facebook Live. Here's the setup:
We've got an hdmi out from a Canon C100 Mark II into an elgato hd60s through usb-c into the streaming pc; it's our webcam. Additionally we have a separate computer's hdmi out running into an aver media live hd2 in the same streaming pc.

For audio, we have a seinheisser lav plugged into a Presonus AudioBox 44VSL audio interface which is connected to the streaming pc through usb. Our issue is that the audio from our mic isn't syncing up to the video from the c100 camera. And when streaming to Facebook Live that sync gets worse. Even if it looks correct in OBS the streamed result doesn't. We've tried correcting this issue using the audio delay feature in the advanced properties in the mixer but we haven't had any luck. Before we ran the stream at 24fps but after moving it up to 30 we've had a lot of problems streaming to Facebook Live.

Any ideas to what can be done to fix these issues? Can the hdmi out from the c100 carry over an audio signal from the lavs into the Aver Media capture card?

Thanks.

 

[TFE]

For two years I've live-streamed over 250 shows (usually 1-2 hours in length) to Facebook using OBS on both an older iMac and recent MacBook Pro. Multiple scenes: usually three webcams, a laptop connected to the streaming computer via BMD Mini Recorder as the source for Powerpoint/Keynote slides and video, and Skype calls also from the laptop connected to the streaming computer via NDI. Am always using an ethernet connection; the iMac with approx 13mbs up, and the MBP with fully 95mbs up. Both sending 720p/30, at a video bitrate of 2500 with the "super fast" encoder preset. I have long since adjusted audio-video sync using a Sync Offset of 140ms under OBS's Advanced Audio Properties, and the sync has been consistently good on FB Lives from both machines though not always perfect. However, something has changed in the past couple weeks, and the video seems to be running even further behind the audio than in the past. So I have to go back and fiddle-fart around doing the trial-and-error to find a new, good Sync Offset. Of course I also record the live-streamed shows to my hard drives on each machine, and that audio-video sync is fine. I'm not sure, but I think the sync when the show is live is ALSO good, but the VOD replays no longer seem to be properly synced. Not sure what has changed except that apparently FB has changed to RTMPS on 1 May. Could that have affected the sync? Or is it something else? If I go to update the sync (and I will), will it then change again sometime down the road? Is it something I am doing wrong? Thanks for any and all suggestions. My most recent live-streamed show "TFE LIVE" from yesterday (2019-05-10): https://www.facebook.com/SailingIllustratedBlog/videos/998284640562141/

 

[Vincent.]

Hello,

So I've been having problems syncing audio with video through OBS. We're streaming on Facebook Live. Here's the setup:
We've got an hdmi out from a Canon C100 Mark II into an elgato hd60s through usb-c into the streaming pc; it's our webcam. Additionally we have a separate computer's hdmi out running into an aver media live hd2 in the same streaming pc.

For audio, we have a seinheisser lav plugged into a Presonus AudioBox 44VSL audio interface which is connected to the streaming pc through usb. Our issue is that the audio from our mic isn't syncing up to the video from the c100 camera. And when streaming to Facebook Live that sync gets worse. Even if it looks correct in OBS the streamed result doesn't. We've tried correcting this issue using the audio delay feature in the advanced properties in the mixer but we haven't had any luck. Before we ran the stream at 24fps but after moving it up to 30 we've had a lot of problems streaming to Facebook Live.

Any ideas to what can be done to fix these issues? Can the hdmi out from the c100 carry over an audio signal from the lavs into the Aver Media capture card?

Thanks.

Any ideas on this one guys?

 

[BrotherRon]

Any ideas on this one guys?

Did you find a fix? Since May, my Facebook audio is out sync with the video.

 

[ARTivationMedia]

Run your mic into the presonus, use a TRS to xlr adapter to send signal from your sound card's main left output to your c100's xlr input. Hdmi will carry audio to your streaming pc. if you don't see your cameras audio, navigate to the c100's source properties in obs, select "control audio via obs".

To use the c100 audio across multiple scenes, simply drop it in below your program source for that scene.

Hope this helps.

 

[Endeavr]

Run your mic into the presonus, use a TRS to xlr adapter to send signal from your sound card's main left output to your c100's xlr input. Hdmi will carry audio to your streaming pc. if you don't see your cameras audio, navigate to the c100's source properties in obs, select "control audio via obs".

To use the c100 audio across multiple scenes, simply drop it in below your program source for that scene.

Hope this helps.

It will not. This is a Facebook issue. The stream is synced, but once it is no longer live, it will go out of sync. I streamed to Twitch, YT, and FB all with no sync issue, and Twitch and YT have no sync issue on VOD, but FB does. So no worries, it is NOT your equipment, but it sadly is an issue FB will never fix. So I suggest restreaming to a separate platform to grab your video, unless you want to attempt recording and streaming on the same PC.

 

[Endeavr]

Run your mic into the presonus, use a TRS to xlr adapter to send signal from your sound card's main left output to your c100's xlr input. Hdmi will carry audio to your streaming pc. if you don't see your cameras audio, navigate to the c100's source properties in obs, select "control audio via obs".

To use the c100 audio across multiple scenes, simply drop it in below your program source for that scene.

Hope this helps.

PS last reply I didn't mean YOUR stuff. I'm new to these forums. DAMN they are glitchy as hell on android.

 

[ARTivationMedia]

It will not. This is a Facebook issue. The stream is synced, but once it is no longer live, it will go out of sync. I streamed to Twitch, YT, and FB all with no sync issue, and Twitch and YT have no sync issue on VOD, but FB does. So no worries, it is NOT your equipment, but it sadly is an issue FB will never fix. So I suggest restreaming to a separate platform to grab your video, unless you want to attempt recording and streaming on the same PC.

Very odd... We stream clients to FB on a regular basis using embedded HDMI audio and have only ever experienced any significant post processing desynchronization when using variable bit rates. Our OBS settings are as follows: X264 encoder, enforce streaming service encoder settings ticked, Rate control = CBR, Bitrate 3750, output resolution 1280 X 720, CPU = Ultrafast, Profile = High, Tune = None.