
In Windows 10 versions released before Windows Update, Microsoft had implemented support for the A2DP source role, but not for the SINK role for desktop editions.

Microsoft provides native support for Bluetooth audio streaming as A2DP source only. Starting from Windows 8, the A2DP Sink role is not supported by Microsoft, nor by third party drivers.

In the release version of Windows 7, your PC could connect to Bluetooth speakers (act as A2DP source) but additionally, drivers could enable the audio device to work as A2DP sink if supported by the audio hardware vendor.

In Windows 7 pre-release versions, A2DP source and sink roles were supported natively but this was dropped in the final RTM release version.
