I've had my sansa sandisk m250 for about 2 weeks, and i set up to my computer and i tried to delete some of the files, and it just won't let me do so!! i'm not to sure whats wrong with it but i would also like some insight on this problem, i've tried everything to delete the files they just wont go away!! plus some of the music on my sansa sandisk m250 skips!! it never use to do this before!!!! please help someone!! thanks for your time !!