Windows 11 KB5077181 Bluetooth and Audio Issues After February 2026 Update

What are the KB5077181 Bluetooth and audio issues?

Windows 11 cumulative update KB5077181 (released February 10, 2026, for builds 26100.7840 and 26200.7840) has introduced peripheral regressions affecting Bluetooth devices, audio output, and HDMI external monitors. Bluetooth adapters disappear from Device Manager without warning, Realtek audio drivers produce popping and crackling sounds on gaming laptops, and HDMI output to external monitors drops signal entirely. These issues are separate from the known KB5077181 boot loop and DHCP failures.

Microsoft has not officially acknowledged these peripheral regressions, but they are widely confirmed on Microsoft Q&A forums, Windows Central, and Neowin. The primary fix for HDMI signal loss is uninstalling KB5077181. Bluetooth and audio issues can be resolved through driver rollbacks and service resets without removing the update.

When does it occur?

• Bluetooth mice, keyboards, and headphones disconnect randomly or fail to pair after installing KB5077181
• Bluetooth adapter disappears from Device Manager with no yellow warning triangle
• Audio produces popping, crackling, or static every 1-2 seconds on laptops with Realtek audio
• System freezes briefly during audio playback on Realtek-equipped gaming laptops
• External monitor connected via HDMI shows "No Signal" after the update
• HDMI signal drops and reconnects intermittently during use

Common causes

• KB5077181 modifies the Bluetooth driver stack, invalidating existing device pairings
• The Bluetooth Support Service startup type may reset to "Manual" after the update
• Realtek HD Audio driver conflicts with updated Windows audio subsystem components
• Microsoft UAA Bus Driver for High Definition Audio conflicts with Realtek on some systems
• KB5077181 introduces a regression in the HDMI output handling pipeline
• Audio enhancement settings become misconfigured after the cumulative update
• GPU display adapter drivers interact poorly with the updated HDMI stack

Step-by-step fixes

1. Fix Bluetooth: Hard power reset — Fully shut down the PC (not restart). Unplug the power cable and hold the power button for 30 seconds to discharge capacitors. Reconnect power and boot normally. Check Settings > Bluetooth & devices to verify the adapter reappears. This is the most effective fix reported on Microsoft Q&A.

1. Fix Bluetooth: Restart Bluetooth services — Press Win + R, type services.msc, press Enter. Find "Bluetooth Support Service," right-click > Restart. Then right-click > Properties > set Startup type to "Automatic." Repeat for "Bluetooth User Support Service." This restores the Bluetooth stack that KB5077181 may have disrupted.

1. Fix Bluetooth: Roll back Bluetooth driver — Press Win + X > Device Manager > expand Bluetooth. Right-click your adapter (Intel Wireless Bluetooth, Realtek Bluetooth, etc.) > Properties > Driver tab > "Roll Back Driver." If greyed out, select "Uninstall device" > check "Attempt to remove the driver" > Uninstall. Reboot — Windows will reinstall the previous driver version.

1. Fix audio: Roll back Realtek audio driver — In Device Manager, expand "Sound, video and game controllers." Right-click "Realtek High Definition Audio" > Properties > Driver tab > "Roll Back Driver." If greyed out, uninstall the device with "Delete the driver software" checked. Reboot and download the last stable Realtek driver from your laptop manufacturer's support page (Dell, HP, Lenovo, ASUS).

1. Fix audio: Disable audio enhancements — Right-click the speaker icon in the taskbar > Sound settings > click your output device > Properties. Under the Enhancements or Advanced tab, check "Disable all enhancements" and click Apply. KB5077181 can misconfigure spatial audio and enhancement settings.

1. Fix audio: Disable Microsoft UAA Bus Driver — In Device Manager > View > Show hidden devices > expand System devices. Find "Microsoft UAA Bus Driver for High Definition Audio," right-click > Disable device. Reboot. This resolves a known conflict where both UAA and Realtek drivers compete for the audio pipeline.

1. Fix HDMI: Uninstall KB5077181 — This is the only confirmed fix for HDMI signal loss. Open Control Panel > Programs and Features > View installed updates. Find KB5077181, right-click > Uninstall. If you cannot boot to desktop, trigger Windows Recovery (interrupt boot 3 times) > Troubleshoot > Advanced options > Uninstall Updates > "Uninstall latest quality update."

1. Pause Windows Updates to prevent reinstallation — After uninstalling or fixing issues, go to Settings > Windows Update > click "Pause updates" dropdown > select "Pause for 5 weeks." This prevents KB5077181 from reinstalling automatically while you wait for Microsoft's corrected update.

If it still doesn't work

For intermittent HDMI signal drops without full loss, press Win + Ctrl + Shift + B to reset the graphics driver without rebooting. For audio that continues crackling after driver rollback, run the built-in troubleshooter at Settings > System > Troubleshoot > Other troubleshooters > Playing Audio. If Bluetooth devices pair but disconnect within seconds, remove all paired devices from Settings > Bluetooth & devices, restart, and re-pair each device individually. Note that KB5077181 includes patches for actively exploited zero-day vulnerabilities — if you uninstall it, keep the pause period as short as possible and monitor Microsoft's release health dashboard for a replacement update. Run DISM /Online /Cleanup-Image /RestoreHealth followed by sfc /scannow in an elevated Command Prompt to repair any system file corruption caused by the update.