Drive problem

Hello,
Can u help please, had problem with my D: drive for a week, my music on D: wont play properly and have been looking at everything i can think of, and i have notice in Disk Management that system (C:) is Disk 1, Samsung (D:) has Disk 0 showing, then my external drive (F:) says disk 2. I am no expert but think that Samsung (D:) should be Disk 2 not the external drive. If possible not too techical an answer.