I'm using a FiiO X1 and for the longest time I've had trouble creating a custom playlist, and the process of adding individual songs to a native FiiO playlist is very tedious. Here's a simple process I just discovered.
For example, I have a main folder called EDM within which I have many sub-folders (A, B, C and D). The FiiO system will only shuffle folder A separately and the same for folders B, C and D. I wanted to shuffle only folders A and B with the help of a playlist.
Creating a playlist using Windows 8.1 and Winamp v5.601
Step 1:
Connect the FiiO X1 to the PC with the USB cable.
Step 2:
In Windows explorer, navigate to My Compuer>X1>EDM
Step 3:
Drag and drop the folders titled A and B into Winamp (make sure that the Winamp playlist section is empty before dropping the folders in it)
Step 4:
In Winamp, go to 'File>Save playlist' (Ctrl+S also works)
Step 5:
Give the playlist a name (eg. 'Favourites.m3u)' and save in on the X1 directly within the main folder (on my X1, I saved it in the main EDM folder)
The .m3u playlist is now displayed in the main EDM folder below the sub-folders A, B, C and D.
Step 6:
To access the playlist:
1. Safely eject the FiiO X1
2. Start up the X1
3. Go to the 'Folder' icon
4. Open the respective folder (in my case the folder 'EDM')
5. Select the playlist which is now below the folders A, B, C and D (in my case the playlist is titled 'Favourites.m3u')
It plays perfectly well!
Further, if you want to delete individual songs, you can follow the same process and open the playlist in Winamp and delete individual tracks and then save again (save directly on to the X1)
I've created multiple playlists within each 'Main' folder (eg. my main folders are listed as Classical Music, EDM, Driving Music etc) for my different moods
In my experience, I did not have to update the 'Media Library' after creating the playlist.
I think this process should work for the X3 and X5 as well.
Hope this is helpful!