Your OBS audio source goes silent when the interface disconnects on a Mac
This is the worst version of the problem, because nothing on screen tells you. The stream is live, the video is fine, the OBS audio meter sits flat at the bottom, and nobody in the room knows until a viewer says something in chat. The interface blipped — a cable, a hub, a power event — and the audio input capture never came back.
Here's why OBS behaves this way on macOS, and how to make a USB blip something your stream survives.
Why the source goes silent and stays silent
An OBS Audio Input Capture source is bound to a specific Core Audio device. When you pick your interface, OBS stores a reference to that device and starts pulling audio from it.
A disconnect removes the device from Core Audio. OBS's source is now pointing at nothing, so it produces silence.
The critical part is what happens next. When the interface returns, macOS re-adds it — possibly with a different internal identity. OBS may not treat the returning device as the same device it lost, so it doesn't re-attach. The source stays exactly where it was: present in the scene, correctly named, and completely silent. Your stream keeps going, which is precisely why nobody notices.
This is also why the standard advice — "just re-select the device" — works but is useless. It works when someone is watching the meters. On a service or a broadcast, often nobody is.
What helps
Re-select the device in the source properties. The reliable manual recovery: open the Audio Input Capture properties, pick a different device, apply, pick yours again.
Put a visible meter where the operator can see it and make "check the audio meter" an explicit part of the run sheet. If the failure mode is silent, add a way to see it.
Harden the physical layer. Direct USB port rather than a hub or a display dock, powered interface, secured cable, current firmware, sleep and USB power saving disabled. Streaming machines are often laptops on docks, which is the highest-risk configuration there is.
Record a local safety copy from a separate device where the stakes justify it.
These reduce the frequency and shorten the recovery. None of them stop the source from silently detaching in the first place.
The durable fix
Point the OBS source at a stable device that mirrors your interface, rather than at the interface directly.
Because the mirror never leaves Core Audio, the OBS source never loses the device it's attached to. There's nothing to detach from and nothing to re-select. When the hardware drops you get a brief gap of silence; when it comes back, audio resumes through the same source OBS has been reading all along — automatically, with nobody touching anything.
For a live stream that's a categorical difference. The failure goes from "audio is gone for the rest of the broadcast unless someone notices" to "there was a short gap".
Keel Audio does this on macOS: a transparent, bit-for-bit mirror of your interface, on its own clock, that stays present across disconnects and re-enumeration. Point OBS at the Keel device once. It's a one-time purchase with a full 14-day trial — test it by starting a local recording and pulling the interface out halfway through.
One clarification, because it comes up: this isn't a router, a virtual cable, or a mixer for moving sound between apps. It does a single job — keep one physical interface rock-stable for whatever depends on it.
A pre-stream checklist
- Interface in a direct port, not the dock that also drives the display.
- Powered interface, secured cable, current firmware.
- OBS pointed at a stable device rather than the raw interface.
- Sleep and USB power saving disabled on the streaming Mac.
- An audio meter visible to whoever is operating.
- A dry run that includes unplugging the interface mid-recording.
Bottom line
OBS going silent after a USB blip isn't an OBS bug — it's a source bound to a device that got deleted and replaced. Make the drops rare, make the meter visible, and give OBS a device that can't disappear. Then the worst case is a gap nobody has to fix mid-broadcast.
Keel Audio keeps one audio interface rock-stable on macOS, so a USB drop never resets your DAW or kills your stream.
Try it free for 14 days →