I2S output mods for Squeezebox

SB Duet receiver: I want to bypass S/PDIF and tap into I2S signal directly so receiver has true I2S out (output connection will need to be HDMI). Objective: to feed Duet receiver into PS Audio PWD, which utilizes I2S via an HDMI input.

Anyone have experience with modding SB to I2S? Who does such mods?