Hi again mojo. thanks for reply.
Before i try your option i noticed that by left-clicking speaker icon on panel the "set volume control" line was "opaque", not selectable! I think it should give me a graphical window like alsamixer, but i can't click the option.
After i added "sound=noconfig" to the line of grub before "quiet" and "noapic" options: the result has been that the error is still present and i found the volume to 0 (a youtue video played without music); so i raise the volume by mouse wheel on speaker icon of the panel (icon acquired color), but again no sound. So i tried mplayer and it's happen a strange thing: the volume (in Mplayer) was set to 0 and, raising it, i obtained audio from youtube vide too.
Therefore the error is still showed in boot phase and the audio notebook works if i raise it in mplayer.
I thought it could be a failed installation of alsa (alsamixer from terminal works: and it shows card: ALI5451 chip: Analog Devices AD1981B)? an hardware conflict with other part?
I don't know if it is useful, anyway here my "lspci":
pak@pak-slitaz:~$ lspci
00:00.0 Host bridge: ATI Technologies Inc RS200/RS200M AGP Bridge [IGP 340M] (rev 02)
00:01.0 PCI bridge: ATI Technologies Inc PCI Bridge [IGP 340M]
00:02.0 USB controller: ALi Corporation USB 1.1 Controller (rev 03)
00:03.0 Modem: ALi Corporation M5457 AC'97 Modem Controller
00:04.0 Multimedia audio controller: ALi Corporation M5451 PCI AC-Link Controller Audio Device (rev 02)
00:06.0 Bridge: ALi Corporation M7101 Power Management Controller [PMU]
00:07.0 ISA bridge: ALi Corporation M1533/M1535/M1543 PCI to ISA Bridge [Aladdin IV/V/V+]
00:0b.0 Ethernet controller: Broadcom Corporation NetXtreme BCM5901 100Base-TX (rev 01)
00:0c.0 CardBus bridge: Texas Instruments PCI1510 PC card Cardbus Controller
00:0f.0 IDE interface: ALi Corporation M5229 IDE (rev c4)
01:05.0 VGA compatible controller: ATI Technologies Inc RS200 [Radeon IGP330M/340M/350M]