hi i recently bought a mp3 player. it was a chinese model of 512mb. it showed 497mb at the beginning. when i connected it to my comp i had seen a couple of files whose names were not readable. also the comp was asking for a format of the drive and i did so. now my problem is that the comp only recognizes 118mb and not 497 as b4. what do i do to use the full 512 mb?