Microsoft has resolved severe lag and stuttering issues with NDI streaming software affecting Windows 10 and Windows 11 systems after installing the August 2025 security updates.

The company confirmed these problems after receiving widespread reports from users who experienced a range of performance issues while using various streaming apps, including OBS (Open Broadcast Software) and NDI Tools.

"Severe stuttering, lag, and choppy audio/video might occur when using NDI (Network Device Interface) for streaming or transferring audio/video feeds between PCs after installing the August 2025 Windows security update," it said.

As Redmond explained at the time, the streaming issues are triggered after installing the KB5063878 and KB5063709 security updates on Windows 11 24H2 users and Windows 10 21H2/22H2 devices.

The NDI team also confirmed this issue, saying that the buggy Windows updates can cause NDI traffic to drop unexpectedly after deployment, with performance problems occurring "only with RUDP connections, while traffic sent or received using UDP or Single-TCP remains unaffected."

On Tuesday, Microsoft released the KB5065426 and KB5065429 to address this known issue on the two impacted Windows versions.

"We recommend you install the latest update for your device as it contains important improvements and issue resolutions, including this one," Redmond said. "If you install an update released September 9, 2025 (KB5065429) or later, you do not need to use a workaround for this issue."

NDI shared a temporary workaround for those who can't immediately deploy this month's Windows updates. This requires changing the NDI Receive Mode to use TCP or UDP instead of RUDP by installing the free NDI Tools pack and setting the 'Receive Mode' option to 'Single TCP or UDP' from the NDI Access Manager app's 'Advanced' tab.

The September 2025 Patch Tuesday security updates address another known issue introduced by the August 2025 Windows security updates, which causes unexpected User Account Control (UAC) prompts and app installation problems for non-admin users.

After releasing the August cumulative updates, Microsoft fixed another known issue causing security updates delivered via Windows Server Update Services (WSUS) to fail with 0x80240069 errors after installing KB5063878.

One week later, it released emergency Windows updates to fix a known issue that broke Windows reset and recovery operations after installing the KB5063875 (Windows 11), KB5063709 (Windows 10), and KB5063877 (Windows 10 Enterprise) updates.