Pb with hda alc883

hello
i ve got a msi m673 b3 and a nVidia Corporation MCP51 High Definition Audio (rev a2) (chipset nvidia alc883) and i ve got no sound...
I known that this card and chipset make pb with unbuntu festy fawn...
I look for a solution for about 3 weeks and no results, yhat ity s the reason i post this thread here (i'm french man),
if you have got a solution,,, thanks a lot
Some information :
cat /proc/asound/cards
0 [NVidia ]: HDA-Intel - HDA NVidia
                      HDA NVidia at 0xfdfb8000 irq 22

00:10.1 Audio device: nVidia Corporation MCP51 High Definition Audio (rev a2)
        Subsystem: Micro-Star International Co., Ltd. Unknown device 3fdf
        Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
        Status: Cap+ 66MHz+ UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR-
        Latency: 0 (500ns min, 1250ns max)
        Interrupt: pin B routed to IRQ 22
        Region 0: Memory at fdfb8000 (32-bit, non-prefetchable) [size=16K]
        Capabilities: <access denied>

stef@stef-laptop:~$ lsmod | grep snd
snd_hda_intel 21912 1
snd_hda_codec 205056 1 snd_hda_intel
snd_pcm_oss 44544 0
snd_mixer_oss 17408 1 snd_pcm_oss
snd_pcm 79876 3 snd_hda_intel,snd_hda_codec,snd_pcm_oss
snd_seq_dummy 4740 0
snd_seq_oss 32896 0
snd_seq_midi 9600 0
snd_rawmidi 25472 1 snd_seq_midi
snd_seq_midi_event 8448 2 snd_seq_oss,snd_seq_midi
snd_seq 52592 6 snd_seq_dummy,snd_seq_oss,snd_seq_midi,snd_seq_midi_event
snd_timer 23684 2 snd_pcm,snd_seq
snd_seq_device 9100 5 snd_seq_dummy,snd_seq_oss,snd_seq_midi,snd_rawmidi,snd_seq
snd 54020 12 snd_hda_intel,snd_hda_codec,snd_pcm_oss,snd_mixer_oss,snd_pcm,snd_seq_oss,snd_rawmidi,snd_seq,snd_timer,snd_seq_device
soundcore 8672 1 snd
snd_page_alloc 10888 2 snd_hda_intel,snd_pcm

Thank a lot for your answer