I have set my default microphone to my yeti. It is connected via the KVM usb port. Under advanced audio propeties in OBS, my Yet is selected. however, it does not show that it hears any sound, unless I add it as a source and use that instance. How do I fix this?
When you define a microphone in Settings → Audio (Global Audio Devices), OBS initializes that device once at startup. If your KVM was switched away or the Yeti was in a "sleep" state during that millisecond boot sequence, OBS "marks" the device list as present but fails to grab the audio stream—resulting in a visible entry in Advanced Audio Properties that registers no sound.
When you add it as a specific Source (Audio Input Capture), OBS re-initializes the device driver on the fly, forcing a fresh handshake which wakes the Yeti up.
Here is how we fix the Global instance so you do not have to clutter your scenes with redundant sources.
1. Hard-Code the Device ID (Escape "Default")
KVM switches constantly shuffle Windows' "Default Communication Device" assignment. If OBS acts globally based on "Default," it will lose the Yeti whenever you toggle the KVM.
- Go to Settings → Audio → Global Audio Devices.
- Disable "Desktop Audio" or others temporarily to isolate the issue.
- Set Mic/Auxiliary Audio explicitly to "Microphone (Blue Yeti)". Do not leave it on "Default."
- Click Apply.
- Crucial Step: If it is already set to Yeti, toggle it to Disabled, Apply, then toggle it back to Yeti and Apply. This forces OBS to re-acquire the USB handle. obs
2. Match the Sample Rates (The "Robot" Prevention)
The Yeti typically defaults to 48kHz, but KVM reconnections can sometimes force Windows to revert a device to 44.1kHz. If OBS expects 48kHz but the device resets to 44.1kHz during a switch, the global audio engine may silence the input to prevent desync/pitch shift.
- In Windows: Open Control Panel → Sound → Recording → Double-click Blue Yeti → Advanced tab. Ensure the Default Format is 2 Channel, 16 bit, 48000 Hz.
- In OBS: Go to Settings → Audio. Ensure Sample Rate is set to 48kHz.
- These must match. If they differ, the Global device often fails silently while a fresh Source instance might attempt to bridge the gap. log
3. The "Audio Nest" Strategy (The Consultant Recommendation)
Since you are using a KVM, relying on OBS's startup initialization (Global Audio) is risky because the hardware state changes while OBS is open. The "Expensive" way to handle this—ensuring 100% reliability—is to move away from Global Audio settings entirely for the mic.
- Go to Settings → Audio and set all Global Devices to Disabled.
- Create a new Scene called "AUDIO COMPOSITE".
- Add your Yeti here as an Audio Input Capture source (since you proved this works).
- Add this "AUDIO COMPOSITE" scene as a Scene Source into your other broadcast scenes (Gameplay, Just Chatting, etc.).
- Why this works: Scene sources (and the devices inside them) persist more reliably than global boot-time configs, and if it ever freezes, you can simply toggle the visibility of the "AUDIO COMPOSITE" scene to force a driver refresh without restarting the stream.
4. USB Power Management (KVM Specific)
Your KVM might be allowing the USB port to "sleep" momentarily, severing the audio stream handle.
- Device Manager → Universal Serial Bus controllers.
- Right-click each "USB Root Hub" or "Generic USB Hub" → Properties → Power Management.
- Uncheck "Allow the computer to turn off this device to save power." this ensures the KVM/Yeti link stays "hot" even if idle.