[Kodi 19] HDMI extractor's audio stopped working

I’ve turned settings → system → audio → stereoupmix to YES (contrary to Passthrough not working in 19.1? (solved) - #14 by Paul_Solecki) and now both movies work. My problems seem to be resolved.

The audio for both movies is off.

Yes, they didn’t help.

Yes, I’ve rechecked the connection and have tried all EDID modes. They didn’t work.

The “switch” in question is Nintendo Switch. I use a HDMI to splitter to channel audio from both devices using one audio cable (my speaker is far away from Vero and Switch). I can draw a diagram to explain if needed.