Sorry for troubling!
I've got a problem with my Buffalo II+IVY.
After assembling I used it for a few months having a good sound and no troubles
and suddenly after an ordinary switching ON it stopped to function (with no external reason) - no sound.
I use it's SPDIF input.
"Lock" LED on the Buffalo II board is ON, but LED D1 on the mounted precision PSU board doesn't light
while D2 does.
The voltages on LEDs are:
D1 - 0,42V; D2- 2,02V.

The voltages on pins on the both sides of precision PSU are symmetrically the same
GND-IN - 5,45V (coming from Placid PSU)
GND-Out - 0.84V (the pins closest to the GND)
GND-Out - 3.29V (external OUT pins - closer to QP3 and QP4 - resp.)

What could happen? Could this problem with Precision PSU destroy DAC?

Can I get an another Precision PSU board separately from the Buffalo II DAC
or could you give me circuit scheme of the precision PSU
with standard voltages to find parts broken
and parts list - to replace them?

Thanks in advance.
Nicolay

Yes, I mean AVCC module.
I should say correctly from the start. Sorry!
Nicolay