Microsoft has published a support article detailing a new issue that causes Bluetooth speakers to not work with PCs that have internal speakers with recent updates for Windows 10 version 1903.
Build 18362.267 RSS
Microsoft today released KB4505903, a cumulative update for the Windows 10 May 2019 Update that brings the build number to 18362.267. As usual when it's not Patch Tuesday, the update is optional.