Playing note with pygame.midi

I'm trying to play a sound with the pygame.midi module. Here is the code I use :

#!/usr/bin/env python

import pygame.midi
import time

pygame.midi.init()

print pygame.midi.get_default_output_id()
print pygame.midi.get_device_info(0)

player = pygame.midi.Output(0)

player.set_instrument(0)

print 'Playing...'

player.note_on(64)
time.sleep(1)
player.note_off(64)

print 'Played'

pygame.midi.quit()

I've found similar codes while searching for exemples, here is the output :

0

('ALSA', 'Midi Through Port-0', 0, 1, 0)

Playing...

Played

PortMidi call failed...

PortMidi: `Bad pointer'

type ENTER...

No sound is played, and I didn't find any info about the PortMidi error which occurs surprisingly after pygame.midi quits.

Do you have any idea? I'm running an debian-based linux distribution if that can help.