This is simple digital volume control module basing on WM8816 chip from Wolfson.

Features: 

• gain range -111.5dB to +15.5dB

• optoisolation

• 0.5dB / 2.5dB gain step size

• THD 0.001%

This is my V1.1 driver board for WMStamp and relay volume projects (and maybe for few more that are coming) ;)

Documentation:

Programming / learning mode

WM STAMP schematic diagram

WM STAMP PCB dimensions

I found WM8816 chip in:
Marantz PM-15S1 Reference Series Integrated Stereo Amplifier
Marantz PM-11S1 Reference Series Integrated Stereo Amplifier