Help with Wav Files

I am new to LMS and I having trouble with LMS detecting WAV files.

If I go to say All Artists when I get to the specific track it says empty

If I go to Music Folder it will play the track and find and use the metadata.

Once one track has been played it will then appear in the albums list etc but there with the duplicate "empty" tracks still showing.

I have rescanned and also cleared and rescanned.

Any ideas?

Many thanks