Echolalia, the repetition of words and sounds, is very common in ASD's, however, it is usually under conscious control, and either used as a means of delaying a response when you don't know what to say to the comment of another person (so you repeat what they said to avoid coming up with your own words), or it is used as a verbal stim; the words or sounds are pleasurable so you repeat them over and over.
What you are describing sounds rather like a vocal tic disorder; it is similar to tourette's syndrome, except a diagnosis of tourette's requires both verbal and physical tics to have been present and debilitating for at least a year. I don't know what the time requirement for a diagnosis of tic disorder is, but you can read about it online; It's a new addition to the DSM-5.
_________________
"Survival is insufficient" - Seven of Nine
Diagnosed with ASD level 1 on the 10th of April, 2014
Rediagnosed with ASD level 2 on the 4th of May, 2019
Thanks to Olympiadis for my fantastic avatar!