How to Sync Audio and Video in OBS

Before you start

Audio and video sync in OBS is adjusted locally on the computer running OBS. No external service is required. The most useful settings are audio offset, monitoring behavior, sample rate, and video timing. Before changing anything, confirm that the camera, microphone, desktop audio, or other capture source is already present in OBS and that the device works outside OBS. A delay that comes from a capture card, wireless microphone, Bluetooth earbuds, or a slow video encoder can affect different sources in different ways, so identify which source is early or late first.

Step-by-step instructions

Create a short test recording with a visible and audible cue, such as a clap or a hand movement, before making changes. This gives you a reference for the direction and size of the delay.

To adjust the sync of an audio input or output device in OBS:

• 1. Open the Audio Mixer panel.
• 2. Select the gear icon next to the source you need to correct, such as Desktop Audio, Mic/Aux, or an audio input capture.
• 3. Choose Advanced Audio Properties.
• 4. Find the Sync Offset column for that source.
• 5. Enter a positive millisecond value to delay the audio, or a negative value to make it play earlier.
• 6. Close the dialog and make another short test recording.

For a video capture source that arrives later than the audio, select the video source in the Sources list, choose Filters, then add or adjust a Video Delay filter. The delay is also measured in milliseconds. This method is useful when a capture card or camera introduces its own visual latency.

Check the audio monitoring path if you hear a delay while monitoring but the recording is correct. Open Settings, select Audio, and review the sample rate and audio monitoring device. OBS works best when all audio devices use the same sample rate, commonly 48 kHz. Mixing 44.1 kHz and 48 kHz devices can cause drift or unexpected delay.

Also confirm that video settings are stable enough for the recording. Open Settings, select Video, and check the frame rate and resolution. Severe rendering lag or an overloaded system can make video fall behind audio over time, while a small fixed offset usually stays constant.

Check the output

Record another short clip and play it back in a media player that can step frame by frame. Look at the moment the cue is heard and compare it with the moment the cue is visible. If the offset is too small to judge reliably, try a larger test movement or a repeating metronome-like sound. When the chosen offset is correct, the same setting should apply to later recordings unless a device, sample rate, encoder, or usb connection changes.

OBS recording format and encoding do not fix a source-level sync problem, but very high encoder load can create variable timing. If the recording is consistently in sync for the first few seconds and then drifts, lowering the output resolution, frame rate, or encoder preset may be worth testing. Keep the original offset change separate from those performance changes so it remains clear what fixed the problem.

Common problems and next steps

If audio slowly drifts more and more, look at sample rate first. Set Windows sound devices, the OBS audio sample rate, and any external audio interface to the same supported rate, usually 48 kHz, and restart OBS before testing again.

If the delay changes each time OBS starts, check whether device initialization order is affecting timing. Keep capture devices connected before opening OBS and avoid changing the default audio input while OBS is running.

If only the preview or monitoring path seems delayed, use a recording to confirm whether the actual output is affected. Monitoring can add latency that is not present in the saved file.

If the audio arrives early for a wireless microphone or Bluetooth output, raise the positive sync offset in Advanced Audio Properties. If a camera arrives late, use a Video Delay filter on that capture source. If ongoing background noise makes it difficult to identify the cue, temporarily reduce the input level of other sources or move closer to the microphone during the test.

For cases that remain inconsistent, treat the fix as two separate timing problems: a fixed offset and a drifting offset. Correct the fixed delay with the audio or video offset tools, then address drift by stabilizing sample rate, usb bandwidth, encoder load, and device connections.