Elgato Facecam Pro 4K A/V Sync and Latency Test

Elgato Facecam Pro 4K A/V Sync Test: Measure Audio Offset for 4K Streaming

The Facecam Pro offset belongs to your exact capture state, not the camera box. Facecam Pro captures 4K/60fps from a 1/1.8-inch Sony STARVIS CMOS sensor, and Camera Hub lets you control exposure, white balance, focus, contrast, saturation, and other image settings.¹ If your browser or app requests 1080p, the camera can deliver a 1080p stream while still using the full sensor workflow; the W3C Media Capture spec says user agents may use downsampling to satisfy track constraints.² At 60fps, each frame is spaced 16.7 ms apart, so the five-clap average gives you a practical sync value for the exact resolution, Camera Hub preset, cable, and port you test.³ Measured offsets vary by machine and configuration, so use your production setup when you record the final OBS value.

Specifications⁴

Connection and browser setup

Connect the Facecam Pro to a USB 3.0 or better Type-C port before opening the test page. USB-IF identifies 5Gbps as one USB 3.x transfer tier, which gives high-bandwidth 4K video more headroom than USB 2.0.⁵ Close Elgato Camera Hub during the test if you want a baseline measurement, or leave it open with your production preset active if you want the production-accurate offset.

Grant camera and microphone permissions when Chrome prompts. The Facecam Pro registers as "Elgato Facecam Pro" in the dropdown. If two entries appear, select the primary hardware entry rather than any virtual device registered by Camera Hub. The virtual device adds an extra software layer between the camera and the browser, which can introduce additional latency that does not reflect the hardware camera path OBS captures directly.

Run the test twice if you want both a baseline and a production offset. For the baseline, close Camera Hub before measuring. For the production offset, open Camera Hub, select your streaming preset, and run the five-clap test again. The production offset is what you enter in OBS. Keeping both values in a note lets you diagnose future changes when you change Camera Hub settings, resolution, cable, or port.

4K baseline versus browser-delivered stream

The baseline value is useful for diagnosing the camera path, but it may not match what OBS receives if OBS is configured for 4K capture while the browser defaults to 1080p. The value you use for live production should come from the same resolution and Camera Hub profile you intend to stream with. When you keep a side-by-side record of baseline and production offsets, you build a reference that makes future troubleshooting faster because you can isolate whether a sync shift came from the camera hardware or from the software processing layer.

Common A/V sync issues with this model

4K image processing is the main reason to measure the Facecam Pro in its actual capture configuration. Elgato lists 4K60 output, H.264 and MJPEG formats up to 2160p60, and Camera Hub controls for focus, exposure, white balance, and image effects, so your preset and resolution can change the pipeline you are measuring.¹

The other common issue is USB bandwidth contention. If other high-bandwidth devices share the same controller, frame delivery can become less consistent and the five-reading spread can widen. Disconnect unnecessary USB devices and retest on a direct USB 3.0 or better port if the spread looks unstable. The Facecam Pro's 4K/60fps uncompressed stream requires substantially more bandwidth than a 1080p camera, so even a single external SSD on the same USB controller can introduce enough contention to widen your five-clap spread by 10 to 20 ms.

USB bandwidth and laptop port conflicts

Laptop USB ports often share bandwidth with other internal devices. When a dock, external drive, capture device, or another high-bandwidth peripheral competes for the same controller, the Facecam Pro may show more jitter in the five-clap readings. Disconnect competing peripherals during the measurement and reconnect them after capturing the OBS value. If your laptop has both USB 2.0 and USB 3.0 ports, always choose a USB 3.0 port for the Facecam Pro because the higher bandwidth tier reduces the chance of frame delivery contention affecting your clap timestamps.

What the test covers

Five clap pairs measure the video-to-audio offset under your current cable, port, resolution, and Camera Hub configuration. The Facecam Pro's 4K pipeline makes it especially important to measure the exact setup you stream with. Because the camera processes 4K frames through its image engine before delivering them over USB, the processing time per frame is higher than a native 1080p camera, and any change in resolution or Camera Hub settings can shift the offset by a noticeable amount.

Copy the OBS Audio Offset value and enter it in OBS Studio under Edit > Advanced Audio Properties for your microphone. The Sync Offset field accepts audio delay in milliseconds, and 1000 ms equals one second.⁶ After entering the OBS sync offset, record a short test clip and clap once near the middle. OBS exposes resolution and FPS settings for video capture devices, so keep your test resolution aligned with your OBS source.⁷ At 60fps, one frame is 16.7 ms, so use frame-by-frame playback to check whether the clap sound and visible hand impact are aligned.³ If the alignment is off, adjust the OBS Sync Offset value in small increments, record another clip, and keep the value that matches your production capture settings.

Verifying Facecam Pro alignment frame by frame

Frame-by-frame playback matters most with Facecam Pro because 4K/60fps makes sync errors easier to spot. If the clap sound lands one frame early or late after applying the measured offset, adjust the OBS Sync Offset by 10 to 15 ms and record again until the sound and visible impact share the same frame. At 60fps each frame represents only 16.7 ms, so even a single-frame misalignment is visible to attentive viewers during slow-motion playback, making this level of precision worthwhile for professional streams.

Independent review testing confirms the Facecam Pro is the first webcam to capture natively at 4K/60fps, with Camera Hub software handling exposure and color adjustments the sensor itself does not apply automatically.⁸ That combination of a larger 4K/60fps frame and active Camera Hub processing is why this camera's typical offset runs higher than the standard 1080p Facecam.

At the resolution you actually stream with, record the check clip after confirming why your browser caps the Facecam Pro at 1080p by default. OBS exposes resolution and FPS settings for its video capture devices, so keep the test resolution aligned with your OBS source before you paste the offset. The Facecam Pro's 4K pipeline makes the exact setup you stream with the only valid one to measure, because a change in resolution or Camera Hub preset can shift the offset by a noticeable amount. Adjust the Sync Offset in small increments if the clip is still off, and keep the value that matches your production capture settings. Measure once per setup.