no more sound

since I upgraded to Ubuntu 9.04 and Musescore 0.9.5 1768, Qt 4.5.0

I tried to start Jack Control, and now Musescore aborts.

here are the messages if I start without Jack:
tux@tux-laptop:~$ mscore
Suspending PulseAudio
no JACK server found
Alsa_driver: the interface doesn't support mmap-based access.
init ALSA audio driver failed
init ALSA driver failed
no audio output found
init audio driver failed
sequencer init failed
AVERTISSEMENT : le processus fils a été terminé par le signal 4

if I start jack audio control, it starts with the message
21:36:08.620 Could not open ALSA sequencer as a client. ALSA MIDI patchbay will be not available.

and then I start mscore
tux@tux-laptop:~$ mscore
Suspending PulseAudio
ALSA lib seq_hw.c:457:(snd_seq_hw_open) open /dev/snd/seq failed: Aucun fichier ou dossier de ce type
no JACK server found
Alsa_driver: the interface doesn't support mmap-based access.
init ALSA audio driver failed
init ALSA driver failed
no audio output found
init audio driver failed
sequencer init failed
AVERTISSEMENT : le processus fils a été terminé par le signal 4
Échec lors de la reprise : Paramètre invalide