The Windows MIDI Integration Feature
Web MIDI is a powerful API that allows web applications running in your browser to interact directly with connected musical instruments, synthesizers, and MIDI controllers. Historically, Google Chrome handled this interaction using its own cross-platform implementation. However, on Windows systems, Google introduced the “Use Windows runtime MIDI API” flag. This flag instructs Chrome to bypass its internal handling and instead utilize Microsoft’s native Windows Runtime (WinRT) MIDI API to communicate with connected devices.
While the WinRT API offers lower latency and better support for modern Bluetooth MIDI devices, it is still a relatively new integration within Chrome and can be unstable on older versions of Windows 10 or with legacy MIDI hardware. If you are a musician or producer using web-based synthesizers (like Soundtrap or Web Audio synths) and your MIDI keyboard is suddenly not being recognized, constantly disconnecting, or crashing the browser when plugged in, the new WinRT API might be the culprit. Disabling this flag forces Chrome to fall back to the older, more broadly compatible MIDI handling method.
How to Turn Off the Windows Runtime MIDI API
You can force Chrome to revert to legacy MIDI handling via the experimental flags menu.
- Open Google Chrome on your Windows PC.
- Click inside the main address bar at the top of the browser.
- Type
chrome://flagsand press Enter. - A page titled “Experiments” will load.
- In the search bar at the top, type Windows runtime MIDI API.
- The specific flag will appear highlighted in yellow. Next to it is a dropdown menu.
- Change the dropdown menu setting from “Default” to Disabled.
- Click the blue Relaunch button at the bottom of the screen.
Upon restarting, Chrome will ignore the modern WinRT API for MIDI connections, which often resolves hardware recognition issues with older USB MIDI controllers.