Beocreate 4 Ch-Amp analogue output pins

Hello HifiBerry Team,

I am very interested to use the analogue output pins mentioned in that post:

https://support.hifiberry.com/hc/en-us/community/posts/360009280917-Beocreate-4-Ch-Amp-with-analogue-Input?input_string=Beocreate%204%20Ch-Amp%20with%20analogue%20output

Can you please share a documentation.

Thank you.

Heinrich