no audio on toshiba satellite pro p100 laptop

[Roger Downing]

Not sure whether this might hint at the solution at all, but there has been a regression from Feisty it seems.
I have a Toshiba Satellite Pro P100-A4E and sound does not work out of the box on any distro I have tried. Here is a brief history of what has worked for me in enabling audio:
Edgy -
Append acpi=off to boot parameters

Feisty -
Append pci=biosirq pci=noacpi noacpi acpi=off to boot parameters
** Following a BIOS upgrade to v3.80 and a modified DSDT from acpi.sf.net sound works without having to disable ACPI **

Gutsy -
Append acpi=off to boot parameters
Using the same DSDT which previously worked no longer works, BIOS version has not changed.