I sent an email out April 27 2007 on this.
I had a hack that only partially worked.
You will notice from your listing the line:
LNKB: BIOS IRQ 10 for 0.31.INTB is invalid.
I believe this your audio. What I found for me was
that the ACPI tables showed only interrupt 5, and 7 as possible interrupts, and thus the error message.
However bios did assign an interrupt, and indeed if not using an APIC, only bios not the O/S will
assign the interrupt, so what it assigns must be
used.
I removed the call to the subroutine that checked
if the bios assigned interrupt was in the ACPI
supplied list, then the audio worked. However
I am getting some distortion in the sound. It
sounds to me like their might still be an interrupt
problem. Look at:
http://mail-index.netbsd.org/tech-kern/2007/04/27/0004.html
for the patch I used.
-- 
Cliff Wright <cliff@snipe444.org>