you don’t have to change any ‘root files’, its simply a matter of placing a file either in a particular patch directory or into a directory which affects all patches.
removal of that file, will then revert back to built-in sound card. (so no damage done)
so the above, shows how to use an alternative sound card.
whilst theoretically possible to have 2 sound cards working, I’ve never got this to work properly - I always get audio glitches. I think there is some issue with audio clock sync. It may be that this is solve-able (as its a known issue) , but id not figured it out.
i admit, it never really was much of an issue for me, since the external audio interface i used, had many more channels - so didn’t really need the ‘extras’ from the organelle.
generally this is a bit on the ‘hacking’ side , as very few users are going to use it, its also takes a bit of ‘fiddling’ with buffer sizes etc.
my approach has to be to have 2 copies of orac setup,
one of which uses my eurorack audio interface, the other the internal soundcard.
i then just launch the one, that i need at the particular time.