The Jellyfish voice is the one that sounds the least like her to me, but I bet that's her too. The Kelvin and Enterprise computer voices are her. I'd put money on it.
X
To me it sounds like they modified her voice electronically. I could be very wrong, but I think she's the Jellyfish too.
<--Sound engineer. Trust me. The Kelvin and Jellyfish are not her.
But I want them to be her. *stomps foot on ground*
And there is only one 'Computer Voice' listed in the credits, if I'm not mistaken.
They probably are her. I didn't know she did the TOS computer voice till a few years ago. So it's not like she can't disguise her voice some.