My test with the "eac3.ac3" preset is OK. I also tried importing a 7.1 AC-3 file and its rendering results in only 6 channels, as expected. Using CinGG's internal engine: it works fine using 6 channels and doesn't work trying to render 7.1 channels. I guess the internal engine also uses E-AC-3. NOTE: I use pipewire as pulseaudio replacement.