1. Create a folder named "My Music" in the NBA 2K14 folder on your computer.
2. Copy the MP3 files of the music you want to add to the "My Music" folder.
3. Launch the NBA 2K14 game and go to the "Settings" menu.
4. Select the "Audio" tab and then click on the "Custom Music" button.
5. Navigate to the "My Music" folder and select the MP3 files that you want to add.
6. Click on the "Add" button to add the selected MP3 files to the custom music list.
7. Click on the "Save" button to save the changes.
The custom music that you added will now be available in the game's soundtrack. You can select it from the "Custom Music" option in the "Music Player" menu.