Line-in?

[Juris3D]

Hello again! It is me again, after a long time :) I am right now very active about retro-hi-fi and light effects at home (many videos on Twitter), so I am taking Your "pianolizer" also out of my shelves and closets :) Still works, as it did (see our other thread, about Rasp image). Now I am thinking how to trick wired "Line-in" input for this? This audio "hat" has two digital mics on board, so, I am afraid there is no way just hook analog inputs signals to those. How would you go about line-in? Or, maybe you already had such solutions you could point to?
EDIT: I see from mic hat description those onboard are actually analog mics. So, hmm, maybe a hope to hook wiring...
EDIT2: I did a quick wiring to one of onboard mics, and - yes, basically working :)
Thank You in advance! :-)