I don't care for the soundtrack in this and I find the vocals to be distracting when I am trying to concentrate on learning. I'd love to remove or disable these and drop in some instrumental mp3s. FLAC, ogg files or whatever from my GOG library. Is there a way to do this?

OK. I see that this functionality is built in, but not accessible until a game is started. I had only entered the pc building tutorial when I posted, but once a new game is started, audio options via the music player on the computer where you read emails allow you to disable soundtrack tracks, select external folders for audio, and access a selection of internet radio from an editable text file in the game directory.