At first you must select all the music you want to listen in the game. Then you have to copy tracks and paste in the needed folder. It can be found on the Disk C: find the folder My Documents, then the main folder with the game and there you need to open the folder named User Music. You don’t need to rename it, just copy all your music there.
Then start the game and press Options. Choose the point Audio and press Confirm scanning. The download will begin. Then enter the game, sit into the car and choose the radio. Now you can listen to your music.