Stream audio sync issue

[gregvs]

I am running into an issue with streaming audio unsyncing and the delay increasing as time goes on. Through a fair amount of observation/trial and error I determined the initial delay to be in the neighborhood of 790ms. No problem, I entered that as a sync offset and it looks perfect. 25 minutes into the stream it is closer to 825ms and 15minutes after that it is approaching 875ms. One additional thing…I used the same setup with a Magewell HDMI to USB interface and had ZERO latency issues. It started as soon as I put the ATEM mini inline. Any thoughts? Any ideas would be a great help.





Equipment listed below with the last log file:


Logfile:
https://obsproject.com/logs/gLV0HiMEE1P0piV3


Blackmagic designs ATEM mini


Panasonic AW-HE40 (audio fed from mixer directly to camera)


OBS Studio 25.0.8

 

[gregvs]

Update:

I went back to the Magewell I have used in the past and fed it with the HDMI out from the ATEM. It instantly solved my audio latency issue and no more drift. I am thinking the encoder portion of the ATEM is maybe lacking a bit in this regard. I will be in touch with Blackmagic and see what they have to say. I was hoping this little gem wasn't too good to be true. Heck for the money I still think it's worth the try!

 

[egav2]

I’m having the same issues! But encountered the problem with all three major capture cards (Atem mini, Magewell, ElGato Hd60S+). My delay wasn’t as bad as yours with the atem but it was worst with the elgato+magewell.

A friend mentioned the issue might come from overheating. I’m getting a cooling pad for my mac mini to see if it helps.

 

[gregvs]

Update: I streamed a number of hour long tests and the issue is definitely ONLY with the ATEM mini. Blackmagic has been very responsive and would like to take the ATEM back and put it on the bench and test. They did not feel heat was in any way related. I've added cooling pads and fans but really doesn't seem to matter. I belive the issue is something related to the encoder in the ATEM. HDMI out works perfectly if I feed it to into the Magewell, the sync issue is gone. Will update results when I have the final word

 

[zburkhardt18]

I'm having the same problems with my ATEM Mini, so I'm following this. I found this issue happens with OBS on MacOS, but when I rebooted into Bootcamp (Windows), everything worked fantastically with Windows OBS on my Macbook Pro.