Windows 11 26H2 feels faster, but an audio bug is crashing some apps

26H2 looks like a boring annual update, and in a sense it is. It's an enablement package, meaning it mostly switches on features that were already delivered through monthly updates, according to Windows Latest.

Microsoft's own what's new page says many of its features "have already been delivered through monthly servicing updates," and that 26H2 "enables selected features and resets the support lifecycle," as quoted by Windows Latest.

The twist: many PCs never got those features before. Microsoft uses gradual rollouts, so two PCs on the same update could behave differently. Since 26H2 rolls everything up, most PCs that move to it should now get the improvements.

The headline feature is the Low Latency Profile. When you open the Start menu, search, the Notification Center or an app, Windows pushes the CPU close to its maximum speed for one to three seconds, finishes the work, and lets the processor drop back to idle sooner, Windows Latest explains.

It's sometimes called "race to sleep," and it targets the small pauses that make Windows feel slow even when the CPU isn't busy.

• June: Microsoft rolled it out for shell elements like the Start menu.
• August: it extended the boost to app launches. In Windows Latest's testing, apps like WhatsApp, Calculator and Weather opened much faster.
• 26H2: both boosts should now be on for most PCs.

In real life If clicking the Start button or opening an app used to come with a tiny pause, you may notice it's gone after installing 26H2.

Some users say yes. Windows Latest installed 26H2 on a three-year-old 16GB laptop and saw RAM use drop by as much as 2GB.

Right after a restart, its laptop showed 7.0GB in use out of 15.7GB, or about 45%. Before, it often crossed 10GB before any apps were opened. Even with Edge, WhatsApp, Teams, Outlook and a 4K YouTube video running, memory use stayed below 90%, compared with about 95% in lighter tests before.

Other users reported similar results, according to Windows Latest:

The catch: results vary, and high RAM use isn't always bad. Windows uses free memory to cache data and releases it when apps need more, Windows Latest notes.

This fits Microsoft's broader push. TechRadar reports that Microsoft said in August that one of its goals is reducing Windows' memory footprint, especially for 8GB PCs, which are becoming more common as memory prices rise.

Microsoft described that aim as "reducing Windows memory footprint to deliver a fast and responsive Windows experience across the PCs customers use every day," according to TechRadar. The company has also announced plans to speed up boot times, make Windows Hello sign-in more responsive and streamline the Windows 11 setup process.

Search is getting attention too. TechRadar says Microsoft is working to make Windows search find files with long compound names, handle typos better and show relevant results after just two typed characters.

Microsoft has confirmed that some apps and games that use Windows' built-in AC-3 (Dolby Digital) audio decoding can crash after installing KB5124010.

That's an optional update released on September 22. The bug affects Windows 11 24H2, 25H2 and 26H2, because all three share the same underlying code, Windows Latest reports. Installing KB5124010 on 25H2 and then upgrading to 26H2 doesn't avoid it.

According to Microsoft, as quoted by Windows Latest:

"Incidence of this issue depends on the activity that these applications perform. In some cases the application can fail to launch, or close without warning."

In other cases, Microsoft says, an app works normally until certain features are used, such as playing music. Born City reports that crashes can be triggered by raising the volume, changing audio settings or using certain audio features.

Probably not most of them. Microsoft says the bug mainly hits older apps, games and media players that rely on Windows' own decoder rather than shipping their own, according to PBX Science. Most modern apps shouldn't be affected.

Microsoft hasn't published a list of affected software. It also says this is separate from September's USB audio bug, where some audio devices stopped producing sound and showed a Code 10 error.

By the numbers, per PBX Science:

September brought a lot of change at once. On September 8, Microsoft released KB5124008 with some of the most-requested features, including a movable taskbar, a resizable Start menu and Bing-free search, Windows Latest reports. The Start menu can now be set to a "Small" size, with the Pinned section and the Recent feed, previously called Recommended, hidden if you prefer a cleaner look.

It was also a huge month for security fixes. Windows Latest says Microsoft patched 974 security issues in September 2026, compared with 86 in September 2025. PBX Science reports that the September 8 update included fixes for two zero-day flaws that were being actively exploited.

Windows Latest adds that Microsoft has said it's using AI to help deploy hundreds of fixes. When a user flagged an Explorer crash after the September update, a Microsoft program manager described it as an "extensive" release, which made the root cause harder to find. An emergency update followed on September 14, and then KB5124010 arrived on September 22 to fix audio and File History problems, according to Born City.

Windows Latest says it also saw black screens and AMD graphics driver errors in its own tests, which Microsoft hasn't confirmed.

Other problems are still floating around. Born City reports that some users continue to see Wi-Fi connections drop, and that the File History backup feature still isn't working properly for some people even after the September 22 update meant to fix it.

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• Expect a snappier PC: 26H2 should switch on faster menus and app launches for most PCs, and may lower RAM use.
• Skip KB5124010 if you rely on older apps: it's optional, so you don't have to install it.
• If an app already crashes: you can uninstall KB5124010 from Update history in Settings, but that also removes its other fixes, PBX Science notes.
• Wait for the fix: Microsoft says it's coming in a future update.