MICROSOFT HAS CONFIRMED an issue with the Windows 10 May 2019 Update (1903) which is borking Bluetooth speakers.
A patch for the current Windows build (KB4509503) which included what was supposed to be a fix for Bluetooth audio issues has actually had the opposite effect, making it impossible to use Bluetooth speakers if you have an internal speaker - it'll simply route everything to your tinny onboard effort no matter what you do.
In some cases, the connection works, but the audio quality is bobbins. In other cases, your device just won't pair/connect at all.
The good news is that there is a workaround while Microsoft tries to work out what it has done exactly, but sufficed to say there's likely to be the dreaded yellow triangle (aka a ‘bang') next to the Bluetooth AD2P device when you check device manager.
Some users have reported that the AD2P service has been removed from the system altogether.
To fix the issue, you'll need to get into a command line and run System File Checker to repair missing & corrupted files. In other words - the patch isn't installing properly and the resulting driver is corrupted. As pointed out at Windows Latest, you'll need to make sure your security is all up-to-date to avoid false positives.
Before it went rogue, the patch was designed to fulfil several purposes beyond the Bluetooth fix - it had bugfixes for Windows Hello, Microsoft Edge, display drivers, screen controls and that's just for starters.
Given that this represents yet another example of one rogue element in a rolled-up update, you'd be forgiven for wondering why on earth Microsoft still persists in using this technique for distribution. Well, you're not alone. We've never liked it and we're in the moral majority.
It's not known how many devices are afflicted with this bug, and Microsoft is yet to confirm when its fix is coming. Quelle Surprise. μ
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