smp/audio on amd64

I thought that the auich audio device got broken for amd64 somewhere along
the line.  Wrong.   It works fine in single processor mode.  When
booting an MP kernel, though, the audio comes out fast... maybe 2x fast?

Any ideas where to look?

  auich0 at pci0 dev 7 function 5 "AMD 8111 AC97" rev 0x03: irq 10, AMD8111 AC97
  ac97: codec id 0x414c4760 (Avance Logic ALC655)
  audio0 at auich0
  ...
  auich0: measured ac97 link rate at 48102 Hz, will use 48000 Hz

Hmmm, perhaps the link rate is still measured wrong when using both
processors... I'll look at that, first.

// marc