I just tossed a .wav onto my Fuze and it played fine, so I don’t know what’s going wrong.
If you haven’t updated the firmware–there are sticky notes with instructions at the top of the forum–then you should.
But basically I just don’t trust anything coming out of Windows Media Player. It keeps trying to automate things and send over hidden information. So instead of trying to figure out what’s going on with the .wav files, I’d suggest deleting them from the Fuze and redoing them as mp3 files, which are much more widely compatible.
For one thing, there’s no reason to use .wav on a little portable player through tiny earbuds–it’s just a waste of storage space. You would be better off ripping to mp3 (at high quality, 192 kbps or above–320 if you are a fanatic).
Are you ripping the albums onto your computer first, and then copying them over? That’s what I’d suggest. Go ahead and use Windows Media Player to rip them to mp3 if you want (the settings are under Rip Music, switch to .mp3 and higher quality), into some folder on your computer.
Then switch the Fuze under Settings/USB Mode to MSC, and just drag-and-drop the album/folder onto the unit. MSC makes it work like a flash drive–none of WMPlayer’s automation or sneaky stuff. You can name a folder ZOSO if you want and drag all the albums into it. With the newest firmware, the Fuze will read information from the ID3 tags that Windows Media Player got online, or navigate by Folders and filenames if you prefer.