Synchronizing with Music Player

Playback can be synchronized with a music player application running on a same computer.

When [Music Player] is selected in Synchronization, a music player application will be launched automatically (if not started yet).
Then playback begins automatically.
Afterwards, playback follows progress of music and locating of music player application.

Music player application offers [Play List] function, in which songs are ordered to be played.
Playback time (location) is calculated by relating the beginning of the first song in the play list to time [ 00:00:00.00 ] .
(Use/Unuse switch of each track (song) is not counted.
Unused tracks should be excluded from a play list (or placed at end of a list))

macOS
On system vesion 10.15 or later: Music app
On earlier system: iTunes app
　is supported.
Although this is a kind of external synchronization, it is possible to start, stop and locate Music app (or iTunes) from this application.
When Music / iTunes starts up, it automatically loads user created play list last used.
To make audio CD is played automatically, scripting is required, such as AppleScript.
The script shown below does this (for iTunes) (or download here (Load Audio CD.app.zip)).

tell application "iTunes"
	set cd to first source whose kind is audio CD
	set pl to first playlist of cd
	set view of first browser window to pl
	play
end tell

To start application program or script when computer start up, specify them in:
[System Preferences] / [Account] / [Login Items]

See help of macOS for more details.

Windows
On Windows, Windows Media Player is used (tested with series 11).
Although this is a kind of external synchronization, it is possible to start, stop and locate Windows Media Player from this application.
When Windows Media Player starts up, it automatically loads play list last used.
To start application program when computer start up, specify them (or link to them) in:
[Start] / [Programs] / [Startup]

See help of Windows for more details.