Windows 11's new version has three known bugs. One of them is your USB headphones.

Windows 11 version 26H2 went out to everyone on 29 September, and the day after, Microsoft's release health page for it had three entries under Known issues. That page is public, it is where the company admits things, and it is worth a look before you let a new version install.

Two of the three are office problems. Credential Guard machine accounts losing their trust relationship with an Active Directory domain is a thing that happens in companies, not living rooms. Black screens after sign-in on Azure Virtual Desktop hosts running FSLogix is the same story. If you have never heard of either, you are not affected.

The third one is yours. USB Audio Class 1.0 devices may stop working after the update: no sound at all, volume controls stuck at zero, sound settings refusing to open, or Device Manager showing "This device cannot start (Code 10)." Class 1.0 is the older, simpler standard, and it covers a lot of cheap USB headsets, desk microphones and small audio interfaces that have been doing their job quietly for years. Microsoft opened this issue on 11 September, has it marked Mitigated, and says a proper fix is coming in a future update. The same bug reaches back through 25H2, 24H2, 23H2 and Windows 10 22H2.

Microsoft's own line is that you should not skip 26H2, because moving within the same servicing branch behaves more like a monthly update than a full version change. That is fair, and it still leaves you with no audio if you happen to own the wrong headset. If sound stops after the update, the device is not broken. Tendvane's driver back-up lets you keep a copy of your working audio driver before anything changes, which makes rolling back a two-minute job instead of a hunt through a vendor's download page.