Variable audio delay?
- Thread starter Rhewtani
- Start date
Synergist
Member
A slowly changing AV delay is indicative of a clocking / reference issue. This can happen when you're using an internal source (i.e., the computer's own reference clock) to synchronise sources. This is also known as "free-running" sync.
What is your Behringer device? Are you able to feed it with the same source of reference clock as your cameras? More information on your external hardware (audio interface, video devices) would be useful.
Typically to avoid these kinds of issues in a professional environment, you have a primary source of reference ("black and burst" or "tri-level sync" are the predominant formats); this is fed over SDI to all audio/video devices including any capture devices, and they reference to that. Some prosumer or cheaper pro-grade equipment doesn't always include a feature to take external sync, so you have to design your capture setup carefully.
It may be that your video is drifting and your audio is OK... But without definitive reference to clock each device, it's hard to tell. Are you applying many effects to your scenes or incoming video? An OBS log is always helpful. https://obsproject.com/forum/threads/please-post-a-log-with-your-issue-heres-how.23074/
What is your Behringer device? Are you able to feed it with the same source of reference clock as your cameras? More information on your external hardware (audio interface, video devices) would be useful.
Typically to avoid these kinds of issues in a professional environment, you have a primary source of reference ("black and burst" or "tri-level sync" are the predominant formats); this is fed over SDI to all audio/video devices including any capture devices, and they reference to that. Some prosumer or cheaper pro-grade equipment doesn't always include a feature to take external sync, so you have to design your capture setup carefully.
It may be that your video is drifting and your audio is OK... But without definitive reference to clock each device, it's hard to tell. Are you applying many effects to your scenes or incoming video? An OBS log is always helpful. https://obsproject.com/forum/threads/please-post-a-log-with-your-issue-heres-how.23074/
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Could you also please upload the log file of this broadcast where the delay increased 0.6 seconds? Here's how...
(Just out of curiosity: how did you manage to keep audio and video in sync while increasing?)
(Just out of curiosity: how did you manage to keep audio and video in sync while increasing?)
I'll be able to pull logs on Sunday. So yeah, the behringer is combining to xlr inputs and sending over usb, while the PTZ Optics cameras are coming in over SDI. The Yamaha TF5 is sending all of the audio into the behringer. Should I start looking for a network based solution for the audio?
-Chris
-Chris
konsolenritter
Active Member
Wait.
We still need you log showing the issue. Aside of that: You should paint the whole picture. (In the moment you're feeding us just bit by bit. That's ungrateful to be honest.)
So how is your technical flow of the camera(s)? How many of them? If you've more than one, how is your video bus/switching realized?
How is the SDI-feed entering your streaming machine?
While issues often arise by using USB, even the possibility that delay may arise from the video bus bar should be mentioned, too.
Did you disabled all your onboard sound while using the behringer as audio device?
We still need you log showing the issue. Aside of that: You should paint the whole picture. (In the moment you're feeding us just bit by bit. That's ungrateful to be honest.)
So how is your technical flow of the camera(s)? How many of them? If you've more than one, how is your video bus/switching realized?
How is the SDI-feed entering your streaming machine?
While issues often arise by using USB, even the possibility that delay may arise from the video bus bar should be mentioned, too.
Did you disabled all your onboard sound while using the behringer as audio device?
Synergist
Member
Completely agree. My suggestion in that sort of scenario would be to do your audio mix through your desk, and then embed the audio into your SDI, if you are capturing the SDI directly into the OBS PC. This inherently synchronises the embedded audio with the video on the wire. If you have something like a Blackmagic or an AJA input card, it's pretty simple to then just take your finished program mix and encode/stream it.
However, please start at first principles, provide the logs and give a more detailed explanation of your entire setup including all points in the audio and video signal paths. There could be something important we're all missing.