Troubleshooting Overlay Issues

This page collects common overlay problems with RaceLab and breaks them into simple checks you can follow step by step. Work through each section calmly – most overlay issues turn out to be window mode, browser source settings, ports, or other software getting in the way rather than a “mystery bug”.

1. Overlays not showing at all

If you open a layout or start a session and see no overlays at all, start with these basic checks:

1. Is RaceLab running?
   Make sure the RaceLab desktop app is actually open (icon in the system tray) and you are logged in.
2. Are you using the correct overlay URL?
   In most cases you should be using RaceLab’s local overlay URL (for example http://localhost:8080 or the layout link shown in the app), not some old bookmark from months ago.
3. Test the overlay in a normal browser first.
   Open the overlay URL in Chrome/Edge on the same PC. If it does not load there, OBS or your game will not be able to show it either.
4. Check game window mode.
   For most sims, overlays only work reliably in windowed or borderless mode. True exclusive fullscreen often hides overlays behind the game.
5. Temporarily close other overlay tools.
   If you also run other overlay software (dashboards, web overlays, telemetry tools), close them as a test to make sure they are not grabbing the same ports or conflicting with RaceLab.

2. Overlay window is blank / stuck on loading

When the overlay window opens but stays blank or says “loading” forever:

1. Check RaceLab’s local page.
   In a browser, open http://localhost:8080. If you do not see the RaceLab overlay UI or it fails to load, the local web server might be blocked or using the wrong port.
2. Port 8080 conflicts.
   Other tools (log analyzers, dashboards, config pages) sometimes run their own web server on port 8080. Only one program can use a port at a time. Close those tools, restart RaceLab and re-test. If needed, change the port in RaceLab’s settings and restart it.
3. Firewall / antivirus rules.
   Make sure RaceLab is allowed through your firewall and any antivirus suite. Overly strict security tools can block RaceLab from listening on the local port it needs.
4. Try a different browser.
   As a test, copy the overlay URL into another browser (for example from Chrome to Edge, or vice versa). If it loads fine there but not in your main browser, you may have an extension or privacy setting blocking it.

3. Overlay appears but has no live data

If you can see the overlay frame (buttons, widgets, layout), but it shows no positions, no car data or “waiting for sim”, then the problem is usually with telemetry, not the overlay itself.

1. Make sure you are on track.
   Many sims only send full telemetry when the car is actually loaded into a session. Sitting in menus or replays often sends limited or no data.
2. Check the game-specific setup.
   Follow the RaceLab “First Steps” guide for that sim – for example broadcasting.json in ACC, telemetry settings in F1, or plugins for LMU / rFactor 2. A missing or broken config file there will mean overlays connect but stay empty.
3. Watch for wrong ports or passwords.
   If a sim sends telemetry over UDP (ACC, F1, AMS2), the port and any password must match between the game and RaceLab. If they differ by even one digit, RaceLab will see nothing.
4. Restart both the sim and RaceLab.
   After changing telemetry settings or installing a plugin, fully restart the sim and the RaceLab app so they read the new settings.

4. FPS drops or stuttering with overlays enabled

Overlays can expose performance issues that were already close to the limit. If enabling RaceLab suddenly causes **FPS drops or stutters**:

• Check game resolution and refresh rate.
  High resolutions (4K) plus multiple monitors can push the GPU hard, especially when overlays are drawn on top. Dropping to 1440p or adjusting refresh rate can stabilise things in some setups.
• G-Sync / FreeSync interactions.
  Combine fullscreen, windowed overlays and variable refresh and you can get weird stutters. Some users report better results with G-Sync limited to fullscreen only and using borderless window mode for the sim, or by carefully matching the G-Sync and window mode settings.
• Reduce the number of overlays.
  Try a simpler layout first – fewer widgets, fewer browser sources. Once that is stable, add extra overlays one by one until you find which one (if any) is causing the biggest cost.
• Check for duplicate browser sources.
  In streaming setups, make sure you do not have several hidden or duplicate browser sources all rendering the same overlay in the background.

5. Triple-screen and aspect ratio problems

Overlays can highlight or trigger existing quirks in triple-screen setups, especially at 4K or custom resolutions:

• Configure triples first, without overlays.
  Get your triple-screen layout stable with no overlays running. Save those settings in the sim, restart the sim, and confirm it is correct.
• Then add overlays on top.
  Once the base rendering is stable, start RaceLab, open your overlays and test again. If things break only when overlays appear, note exactly which sim, resolution and layout you are using.
• Check for game-specific bugs.
  Some sims have known issues where changing video settings or switching between full-screen and windowed can break triples when overlays are active. In those cases, restarting the sim and sticking to a stable window mode often helps until the game itself is patched.

6. VR overlays not visible or stuck to your face

VR adds another layer of complexity. If overlays are not visible in VR, or they are stuck in a strange place:

1. Confirm VR-specific instructions.
   Some overlays are designed for flat screens first. Always check the RaceLab VR documentation for the sim you are using and follow any specific VR steps or limitations.
2. Check if overlay is in the correct view (mirror vs headset).
   Depending on how the overlay is injected, it may show in the mirrored desktop window instead of inside the headset, or vice versa. Test both.
3. Try a simpler VR overlay layout.
   Start with the smallest, simplest overlay that is confirmed to work in VR for your sim, then build up from there.

7. General “reset” strategy

If you are completely stuck, a clean reset can save hours of frustration:

1. Pick just one sim and one simple layout to test.
2. Close all other overlay or telemetry tools.
3. Verify the sim is in the correct window mode and telemetry is set up exactly as the official RaceLab guide shows.
4. Restart PC, start RaceLab, start the sim, go on track, open your test layout.

Once that baseline works, add complexity back one step at a time: more overlays, other tools, different layouts, streaming PC, VR, and so on.