I'am a newby on raspberry...
I have mount a HiffyBerry Digi I/O on a RPi3B+ and works on last Raspian version.
I would like to connect the SPDIF Optical input to my pc and redirect the signal to the SPDIF Optical Output like as a passtrough mod.
I have configure the output and I can listen music from raspian.
The signal from my pc is ok, red at the cable output.
At the arecord -l command the card is recognize.
pi@raspberrypi:~ $ arecord -l
**** Liste des Périphériques Matériels CAPTURE ****
carte 1: sndrpihifiberry [snd_rpi_hifiberry_digi], périphérique 0: HifiBerry Digi HiFi wm8804-spdif-0 
Sous-périphérique #0: subdevice #0
Maybe I have done something wrong or forgot to configure something.
Could you help me ?