---
title: "OBS Audio Delay: Set the Sync Offset | sync.video"
description: "Fix OBS audio out of sync with a webcam or capture card: measure the delay from a clap test recording and enter it as the source’s Sync Offset in milliseconds."
url: https://sync.video/obs-audio-delay
---

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# Fix OBS audio delay with the right Sync Offset

Record a quick clap, let the tool measure how far the picture lags the sound, and type that number into the microphone’s Sync Offset.

To fix audio delay in OBS, give the audio source a **Sync Offset** equal to how late the picture is. Webcams and capture cards usually deliver their picture after the microphone delivers the sound, so the voice comes first; delaying the microphone by that many milliseconds lines them up. The setting is in **Advanced Audio Properties**, opened from the Audio Mixer’s menu.

Guessing the number takes many test recordings. Measuring it takes one: record a few seconds of yourself clapping, open the recording above, and press **Detect automatically** or use **Jump to the clap** and **This frame is the clap**. The **Sound offset** it shows is the number to type into OBS, and **Copy ms** puts it on your clipboard.

Why a clap works: the sticks meet on one frame and make one sharp spike in the sound. Lining the spike up with that frame syncs everything after it.

## How to measure and set the OBS Sync Offset

1. ### Record a clap test
In OBS, record five seconds of yourself clapping clearly in front of the camera, with the microphone you normally use. Use the same resolution and frame rate you stream at.
2. ### Measure it here
Open the recording above and press **Detect automatically** (A), or **Jump to the clap** (C), step to the frame where your hands meet with , and . and press **This frame is the clap** (K).
3. ### Copy the number
Read the **Sound offset**. A positive value such as +120 ms means the sound must play later. Press **Copy ms**.
4. ### Enter it in OBS
In the Audio Mixer, open **Advanced Audio Properties**, find your microphone and type the number into its **Sync Offset** (ms). Record another clap to confirm it now lines up.

## Why OBS audio and video drift apart

__Common sources of delay in a streaming setup (typical, varies by device)__
| Source                           | What delays                                                   | Usual fix                                                                       |
| -------------------------------- | ------------------------------------------------------------- | ------------------------------------------------------------------------------- |
| USB webcam                       | Picture: the camera compresses and sends frames after capture | Sync Offset on the microphone                                                   |
| Capture card (consoles, cameras) | Picture: buffering in the card                                | Sync Offset on the microphone and on the capture card’s own audio if it differs |
| Bluetooth or wireless microphone | Sound: wireless buffering                                     | Delay the video with a Render Delay filter, or switch to a wired microphone     |
| Game or desktop sound            | Usually nothing                                               | Leave at zero; set only the sources that are wrong                              |

Each source has its own offset, so a webcam and a capture card can need different values. Measure each pairing separately: clap in front of the webcam for the microphone’s offset, and use a game sound or a hand in front of a camera on the capture card for its own.

## Sync Offset in practice

### Which way the number goes

Sync Offset delays the source it is set on. When the voice comes before the lips, the microphone needs a positive offset. When the sound arrives after the picture (rare, usually a wireless microphone), there is nothing to delay on the audio side; add a **Render Delay** filter to the video source instead, with the measured number.

### What it doesn’t cover

* The audio monitoring device (what you hear in your own headphones) has no sync offset; it doesn’t affect the recording or stream.
* Drift over a long session points to a sample-rate mismatch between devices: set them all to the same rate (48 kHz is the usual choice) in their own drivers and in OBS’s audio settings.
* A recording that is already out of sync can still be fixed afterwards: open it in the [audio sync fixer](https://sync.video/fix-audio-sync) and export a corrected copy, no new recording needed.

## Checking the result

1. Record another short clap test with the new offset.
2. Open it here and press **Detect automatically**. A result within a few milliseconds of zero means OBS is set.
3. Repeat whenever you change camera, resolution, frame rate or capture card: each change can alter the delay.

For live streams, the same offset carries to the stream, but viewers watching on headphones or a TV may add their own delay; that part is theirs to fix ([YouTube viewers](https://sync.video/youtube-audio-out-of-sync), [Bluetooth listeners](https://sync.video/bluetooth-audio-delay)). To check your own headphones, the [audio delay test](https://sync.video/audio-delay-test) gives a figure in milliseconds.

## Questions about OBS audio delay

### Where is Sync Offset in OBS?

Open **Advanced Audio Properties** from the Audio Mixer’s menu. Every audio source has a **Sync Offset** field in milliseconds.

### Should the Sync Offset be positive or negative?

Positive delays that source. If your voice comes before your lips move, give the microphone a positive offset equal to the measured delay.

### How do I know how many milliseconds to enter?

Record a clap, open it in the tool above and read the **Sound offset** after **Detect automatically** or the clap method. That number is the offset.

### Why is my webcam behind my microphone?

Cameras compress and buffer their picture before OBS receives it, while a microphone delivers sound almost at once. The gap depends on the camera, its resolution and frame rate.

### My recording is already out of sync. Do I need to record again?

No. Open the recording in the [audio sync fixer](https://sync.video/fix-audio-sync), set the offset and export a corrected copy; the picture is copied, so nothing is lost.

### Why does OBS audio drift out of sync over time?

Usually because devices run at different sample rates or clocks. Set them to the same rate; for a recording that already drifts, use two sync points on [fix audio drift](https://sync.video/fix-audio-drift).

## More in fix audio sync

* [ Fix audio and video out of sync Work out whether the file or the playback is at fault, then fix the delay or measure it. ](https://sync.video/fix-audio-sync)
* [ Test your audio delay A flash and beep, a microphone chirp or tapping: a latency figure in milliseconds. ](https://sync.video/audio-delay-test)
* [ Fix YouTube audio out of sync Browser and app fixes for viewers, and a corrected file for creators before upload. ](https://sync.video/youtube-audio-out-of-sync)
* [ Fix audio that slowly drifts Two sync points stretch the sound so it stays in step from start to end. ](https://sync.video/fix-audio-drift)
* [ Sync audio and video online Drop one video to fix its delay, or several files to line them up by their sound. ](https://sync.video/)