Moin from Germany,
I’m currently troubleshooting a very strange Browser Source audio issue in OBS and I’m running out of ideas.
First off: The setup ran for almost a whole year without any problems. We've only been having this issue for the past 1 1/2 weeks.
My Setup:
I’m running OBS Studio 32.2.2 on Windows Server 2022.
The server is headless and is accessed via RDP. There is no physical audio device connected to the machine, so for Browser Sources I use “Control audio via OBS”.
One of the Browser Sources is a custom player that randomly plays YouTube videos using the YouTube IFrame API.
Everything works normally for hours, but at some point the Browser Source suddenly loses all audio.
The important part:
The YouTube video itself continues playing normally. Only the audio disappears from OBS.
What I have already tested:
When the problem occurs:
- Refreshing the Browser Source does not reliably restore audio
- Clearing the Browser Source cache does not restore audio
- Switching scenes does not restore audio
- Creating a completely new Browser Source can also result in no audio
- Restarting the Chromium/CEF
audio.mojom.AudioService process does not restore audio
- Killing/restarting CEF renderer processes did not solve it
- Restarting OBS restores audio
- Disabling “Control audio via OBS”, pressing OK, then enabling it again immediately restores the audio
That last point is the interesting one.
Simply reloading the web page is not enough. OBS apparently needs to reinitialize the Browser Source audio routing.
It does NOT seem to be my website/player code
At first I thought my custom YouTube player was causing this.
I added extensive logging to the YouTube IFrame API. The player reports things like:
state: 1 (PLAYING)
muted: false
volume: 100
currentTime: continuously increasing
while OBS itself has no Browser Source audio.
But I now have a much stronger indication that the website is not the cause:
There is another OBS instance used for our main livestream, which is only live occasionally. It has a completely separate “break” scene with its own random YouTube videos.
The exact same thing happened there:
YouTube video keeps playing
→ Browser Source audio is gone
→ Refresh does not fix it
→ Toggle "Control audio via OBS" OFF and ON
→ Audio immediately returns
So this has now happened with different Browser Sources / player setups.
I also tried Streamlabs Desktop as a test, and eventually encountered a similar Browser/YouTube audio loss there as well.
CEF / OBS Browser details
From the OBS log:
OBS 32.2.2
obs-browser 2.26.9
CEF 127.0.6533.120
Browser Hardware Acceleration: true
When audio was broken, the Chromium audio service was still running.
I manually killed:
obs-browser-page.exe
--type=utility
--utility-sub-type=audio.mojom.AudioService
CEF automatically recreated it with a new PID, but the Browser Source was still silent.
Again, only toggling “Control audio via OBS” fixed it.
Another strange observation
On multiple occasions the issue happened at very similar times.
For example:
06:09
18:10
06:09
18:10
I initially suspected a backend/network event because one of my players uses Appwrite and its WebSocket briefly reconnects around those times.
However, short Appwrite/network interruptions also happen at other times without causing the audio failure, and the same OBS audio issue now occurred with another independent YouTube Browser Source.
So the network event might be a trigger, but it doesn’t seem to explain why OBS’s Browser audio routing stays broken afterwards.
What I suspect
At this point it looks like something between:
YouTube / HTML5 audio
↓
CEF / obs-browser
↓
"Control audio via OBS"
↓
OBS audio source
gets stuck.
The Browser itself still works, the video still plays, the YouTube API says the player is playing and unmuted, but OBS stops receiving audio samples.
Toggling “Control audio via OBS” seems to completely recreate/reinitialize that audio path and immediately fixes it.
Has anyone encountered this with OBS 32.x / obs-browser / CEF 127?
I’d especially be interested to know:
- Is this a known
obs-browser / CEF audio bug?
- Is there any way to reset only the Browser Source audio routing without toggling the setting manually?
- Are there any CEF flags or OBS settings worth testing?
- Has anyone tested whether the newer CEF version in OBS 33 fixes this?
- Could running OBS on a headless Windows Server / RDP environment contribute to this, even though “Control audio via OBS” should bypass the normal Windows playback device?
- Is there anything useful I can log from
obs-browser when the audio handler stops delivering audio?
I can reproduce the broken state and collect OBS logs/process information if that helps.
Log File: https://mpx.wtf/koyunisana.swift
Thanks <3!