Microsoft has acknowledged a new complication stemming from the Windows 11 August 2025 Security Update, specifically impacting streaming applications. Users may experience “severe stuttering, lag, and choppy audio/video” when utilizing the Network Device Interface (NDI) for streaming or transferring feeds between PCs. The company noted that this issue particularly affects popular streaming software such as OBS (Open Broadcaster Software) and NDI Tools, especially when the ‘Display Capture’ feature is activated on the source PC.
Understanding NDI and Its Role
NDI is a cutting-edge specification designed to facilitate the transmission of high-definition video over computer networks with minimal latency and exceptional quality. It has become a staple in the realms of video production and broadcasting, enabling a multitude of products and organizations to enhance multimedia experiences and streamline setups through IP technology.
However, users who have installed the August 2025 Security Update may find their streaming capabilities compromised. This issue affects various versions of Windows, including Windows 11 24H2, Windows 10 22H2, and Windows 10 21H2. The root of the problem lies in the Reliable User Datagram Protocol (RUDP), the default communication method for NDI. RUDP is designed to merge the low latency and simplicity of UDP with the reliability of TCP (Transmission Control Protocol), making it ideal for real-time multimedia applications where timely data delivery is paramount.
For those who have encountered difficulties post-update, Microsoft suggests switching to TCP or standard UDP as a workaround. Alternatively, users can consider uninstalling the August 2025 Security Update, although this approach carries its own risks, including the possibility that Windows may automatically reinstall the update in the future.
For NDI users who have not yet received the update, the recommendation is to postpone installation until a resolution is provided. Unfortunately, there is currently no timeline for when a fix might be available, as Microsoft continues to investigate the matter.
The August 2025 Security Update has been a challenging chapter for Microsoft, marked by installation failures and the need for urgent out-of-band patches to address bugs introduced by the update. While the latest issue affects only a subset of users, it underscores the complexities Microsoft faces in rolling out updates without inadvertently disrupting essential functionalities relied upon by many.
