Words exist for me in the space beyond my lips, or my fingertips; what that feels like, in the moment, is that it is the act of externalization of words which makes them come into being, but not for a moment are they ever out of my control.
I can't remember the sound of my mother's voice. Not really. Of course if I heard it in a recording it would be as recognizable as any voice, and in fact when I watch animated shows, like classic King of the Hill for example, I'm extremely good at picking out all the celebrity voices and I'm often surprised that I can identify a voice I didn't know that I knew.
I used to have an internal monologue. I used to be able to picture things. That all went away in my teens. Not only can I somewhat remember what that was like, I'm able to experience vivid internal pictures and internal sounds sometimes in the moments just before I'm fully asleep. It doesn't happen very frequently, but it's enjoyable when it does.
And that's it. If you have any questions for thisaphantasic non-self-speaker, have at it.