The Italians actually have a name for that kind of gibberish talking that sounds real. I did some VO work on a project being directed by an Italian guy and he explained what he wanted me to do by explaining the term to me first. I’m afraid it’s been way too long since he told me for me to remember it though.

Another example would be the La Linea cartoons, where the main character speaks a gibberish which seems to approximate Italian to my ears.

www.youtube.com/watch?v=ldff__DwMBc