Songs listed but not playing

I am having trouble playing certain songs on the express.  Firstly, when I go into the album menu and click on the album it list all the tracks correctly but, when I play them, certain songs aren’t playing at all.  When I go through songs or artists  the same thing is happening.  The tracks are DEFINITELY on the player.  This has happened just after I formatted the internal and micro sd card.  Also for some absolutely bizarre reason all the tracks I’ve found so far that don’t play begin with the letters “V” and “W”.  I’m really not kidding.  I’m getting more and more frustrated with the machine and its numerous glitches. 

Actually I think it’s this problem :