Which sound do you mean ?
With one output connected to the audio amplifier u create only Square wave with different frequencies using PWM technic or software based technics .
IF u try harder maybe you could play WAV files using external DACs or ladder Resistors, but about MP3 files I dont think so .
What kind of video do you mean ? Do u want to drive a grafic lcd or u want to PLAY MPEG file !!!!!