From your other comment with the parent's feedback - > She couldn’t tell a difference. My husband and I could tell it was different [...] I wonder if the chil

From your other comment with the parent's feedback - > She couldn’t tell a difference. My husband and I could tell it was different [...] I wonder if the child will eventually be able to tell the difference, when the machine-generated audio is a large fraction of what they hear in their early years. Or if they just learn to consider that 'normal', and maybe model their own speech patterns after it. Also, anecdotes from parents (is that what you're referring to by "clear empirical evidence"?) are not evidence.