The only way to add playlists on this unit is to use your PC software to create them and then add to the unit later. you cannot create a playlist on the player itself.
you can use any music software to create and add. for instance, If you are using Sonys own Soundstage, follow these instructions:
Click "My Library"
Click "create/edit PLaylist"
Select the tracks you want from content shown on left. ( to select multiple tracks at once, hold CTRL key)
Select the "New Playlist" on right
The new playlist will be created. you can rename it now
click on large arrow pointing left
Now just import this folder to your player
you are done.
Here is a link to the user guidehttp://www.docs.sony.com/release/NWHD5_english.pdf
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