(Image credit: Future) With its latest update for Windows 11, codenamed KB5089573 , Microsoft has finally started to fully roll out something that it began late last year, and something that phones have supported for even longer. It's a Bluetooth feature called Shared Audio , and as long as everyone's hardware ticks off the right boxes, you'll be able to cast music and the like to two separate devices. I always keep Windows on my main PC fully up-to-date, for work reasons, but I wasn't aware that Microsoft had finally rubberstamped the new feature until I read about it at Windows Latest . Unless you had a PC from a very narrow list of options and used a beta version of Windows, there has been no way to have more than one headset playing the same Bluetooth audio stream on a Microsoft-based computer. That changed last year, when Redmont released a preview of Shared Audio , but now every Windows 11 user gets it.…