--- title: Achieving Frame-Accurate Sync Between Display Servers description: Methods and troubleshooting for synchronizing video playback across multiple WATCHOUT display servers. --- [Skip to content](https://knowledge.dataton.com/knowledge/achieving-frame-accurate-sync-between-display-servers#main-content) English Show submenu for translations ![DATATON LOGO 2000.png\]](https://knowledge.dataton.com/hs-fs/hubfs/DATATON%20LOGO%202000.png?height=42&name=DATATON%20LOGO%202000.png) Open main navigation Close main navigation - English Show submenu for translations - Contact us Contact us Hello. How can we help you? - There are no suggestions because the search field is empty. 1. [Knowledge Base](https://knowledge.dataton.com/knowledge?hsLang=en) 2. [WATCHOUT 7](https://knowledge.dataton.com/knowledge/watchout-7?hsLang=en) 3. [Stage & Display](https://knowledge.dataton.com/knowledge/watchout-7?hsLang=en#stage-display) # Achieving Frame-Accurate Sync Between Display Servers ## Achieving Frame-Accurate Sync Between Display Servers Overview When running a multi-server WATCHOUT setup, all display servers must be synchronized to ensure seamless video playback across outputs. WATCHOUT provides multiple synchronization methods. ### Sync Methods ###### 1. NTP-Based Sync (Default) WATCHOUT uses NTP (Network Time Protocol) for timeline synchronization by default. - The **Director** machine acts as the NTP reference. - All **Runners** (display servers) sync their timeline clocks to the Director. - This provides millisecond-level accuracy, sufficient for most setups. ###### **Requirements:** - All machines on the same network - Stable network connection (wired, not WiFi) ###### 2. Hardware Genlock (Quadro Sync II) For frame-accurate sync (required for seamless edge blending): - Use **NVIDIA Quadro Sync II** cards with compatible GPUs (e.g. NVIDIA A6000, RTX A-series) - Configure **sync groups** in WATCHOUT to define which servers sync together - One server acts as the sync source; others follow **WATCHPAX 62/64:** These units have BNC sync connectors. Connect to an external sync generator (e.g. Blackmagic Sync Generator) or daisy-chain between units. ###### 3. NVIDIA Mosaic Mode For outputs spanning multiple display ports on the same GPU: - Configure Mosaic in NVIDIA Control Panel before starting WATCHOUT - Combined with Quadro Sync II for multi-server setups ###### Setup Steps (WATCHPAX 62/64) With the R30 image and the **WATCHPAX Config Tool**: - Open the WATCHPAX Config tool - Configure Mosaic/Sync/EDID settings - Select which unit is the **sync source** and which units follow - No external sync generator is required for basic 2-unit sync — one unit drives the other See the WATCHPAX 64 User's Guide for detailed Config Tool instructions. ### Troubleshooting ###### Stuttering/Choppy Playback Across Servers - **Check NTP:** In Producer, look at the Nodes window. Verify "NTP Diff" is near zero for all runners. - **Check sync groups:** Ensure all servers in a sync group have stable connections (7.7.1 fixed a sync group bug from 7.7.0). - **Check cables:** A faulty BNC cable or network cable can cause intermittent sync drops. - **Check hardware:** A failing WATCHPAX unit can cause the entire sync group to stutter when it drops in and out. ###### NTP Shows "N/A" - The Runner service may not be running — check that the display software is active. - Restart the Director/Manager after any system time changes. - Do NOT change the system clock during playback. ###### Sync Groups Not Working (7.7.0) This was a known bug in WATCHOUT 7.7.0. **Update to 7.7.1** which contains the fix. Confirmed working with NVIDIA A6000 + Quadro Sync II (firmware 306, driver 582.16). ###### Best Practices - Use **wired Gigabit Ethernet** for all sync communication - Set BIOS clocks on all machines to the correct time - Avoid changing system time during operation - If using NTP sync on an isolated network (no internet), the Director's clock is the reference — ensure it's accurate - For critical installations, use hardware genlock (Quadro Sync II) for frame-level accuracy *Last updated: 30 March 2026 · Dataton Support* - [WATCHOUT 7](https://knowledge.dataton.com/knowledge/watchout-7?hsLang=en#main-content) - [Installation](https://knowledge.dataton.com/knowledge/watchout-7?hsLang=en#installation) - [Stage & Display](https://knowledge.dataton.com/knowledge/watchout-7?hsLang=en#stage-display) - [WATCHPAX media servers](https://knowledge.dataton.com/knowledge/watchout-7?hsLang=en#watchpax-media-servers) - [Licensing](https://knowledge.dataton.com/knowledge/watchout-7?hsLang=en#licensing) - [WATCHOUT 6](https://knowledge.dataton.com/knowledge/watchout-6?hsLang=en#main-content) - [Capture](https://knowledge.dataton.com/knowledge/watchout-6?hsLang=en#capture) - [Dynamic Image Server](https://knowledge.dataton.com/knowledge/watchout-6?hsLang=en#dynamic-image-server) - [Graphics Card](https://knowledge.dataton.com/knowledge/watchout-6?hsLang=en#graphics-card) - [Network](https://knowledge.dataton.com/knowledge/watchout-6?hsLang=en#network) - [Operating System - Windows](https://knowledge.dataton.com/knowledge/watchout-6?hsLang=en#operating-system-windows) - [Video Encoding](https://knowledge.dataton.com/knowledge/watchout-6?hsLang=en#video-encoding) - [Timeline](https://knowledge.dataton.com/knowledge/watchout-6?hsLang=en#timeline) - [Control](https://knowledge.dataton.com/knowledge/watchout-6?hsLang=en#control) - [Installation](https://knowledge.dataton.com/knowledge/watchout-6?hsLang=en#installation) - [Audio](https://knowledge.dataton.com/knowledge/watchout-6?hsLang=en#audio) - [Camera Calibration](https://knowledge.dataton.com/knowledge/watchout-6?hsLang=en#camera-calibration) - [Synchronization](https://knowledge.dataton.com/knowledge/watchout-6?hsLang=en#synchronization) - [WATCHPAX](https://knowledge.dataton.com/knowledge/watchpax?hsLang=en#main-content) - [Audio interface](https://knowledge.dataton.com/knowledge/watchpax?hsLang=en#audio-interface) - [Network](https://knowledge.dataton.com/knowledge/watchpax?hsLang=en#network) - [Installation](https://knowledge.dataton.com/knowledge/watchpax?hsLang=en#installation) - [WATCHNET](https://knowledge.dataton.com/knowledge/watchnet?hsLang=en) [![DATATON LOGO 2000 black](https://knowledge.dataton.com/hs-fs/hubfs/DATATON%20LOGO%202000%20black.png?width=200&height=46&name=DATATON%20LOGO%202000%20black.png "DATATON LOGO 2000 black")](http://dataton.com) Need to register a support ticket? 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