kenwood kdc-hd548u

Kenwood KDC-HD548U. I bought a used car (3000gt) with the Kenwood KDC-HD548U already in it. I made a cd with MP3 file types and according to the Kenwood site it should be able to read MP3, WMA or AAC files. however after giving up on MP3 Files i tried ACC with no different results. So i...