It's pretty slow. I wonder if they're just getting people used to her voice before speeding it up, though it's pretty intelligible. Is this new for LA County or have they used it before?
Sounds like a real person to me. You can hear background noise being picked up by the mic. Puffs of air going into the microphone when she speaks. Inconsistent pauses. I could be wrong but it sounds like a real person to me.
Maybe they were testing it, or maybe it had something to do with how busy it is right now with the fires, but they seem to have gone back to live voices for dispatch.