Windows 10 does not, however, support volume change based on system sleep or boot states.

This setting is not device-specific but rather port-specific i.e., the volume is set for devices that are connected via the audio jack. Likewise, users can set app specific volumes and Windows 10 will remember it. If you connect a pair of headphones to your system and set the volume to, for example, 50, Windows 10 will automatically change the volume to 50 the next time you connect the headphones to your system. Windows 10 can remember the volume that was set for an audio device, and for a particular app.