See also:

Notes On Playing MP3 Files
The radio can play MP3 files; however, acceptable MP3 file recording media and formats are limited. When writing MP3 files, pay attention to the following restrictions. ...

DISC Button
Pressing the DISC button will allow you to switch from AM/FM modes to Disc modes. ...

Commands
The Voice Command system understands two types of commands. Universal commands are available at all times. Local commands are available if the supported radio mode is active. ...