No desktop audio in OBS

Confirm what OBS is listening to

Open Settings → Audio and set Desktop Audio to the specific output device you actually hear, rather than Default. "Default" follows the operating system, so plugging in a headset mid-session silently changes what OBS captures. After changing it, check that the Desktop Audio meter moves while sound is playing.

Exclusive mode

On Windows, an application that takes exclusive control of the audio device prevents OBS from capturing it. In Sound settings, open the device properties and clear "Allow applications to take exclusive control of this device" for both the playback device and any loopback device you use.

Muted, hidden or routed elsewhere

• Check the Windows Volume Mixer: the game may be muted at the per-application level.
• Check that the Desktop Audio track is not muted in the OBS Audio Mixer, and that its slider is not at the bottom.
• In Advanced Audio Properties, confirm the source is assigned to the audio tracks your output actually uses. A recording with only track 1 enabled will be silent if desktop audio is assigned to track 2 alone.

macOS has no built-in loopback

macOS does not expose system audio to applications by default. Recent OBS versions include a macOS screen capture source that can include application audio; otherwise a virtual audio device is required. Capture the application audio you need rather than the entire system where possible, because it keeps notification sounds out of the recording.

Linux

With PipeWire or PulseAudio, add an Audio Output Capture source and select the monitor of your output device. The monitor device is what carries what is being played; selecting the output device itself captures nothing.