Zzzap allows Maxwell to speak through radios

He focused on the stereo again.
The speakers popped and said, “Work this time?”
Got it, said Zzzap.
“Oh my God,” said the stereo. “I was starting to think I’d never hear my own voice again.” There were a few quick snaps and a squelch of static. “Can you all hear me okay? You can understand me?”
St. George looked at Zzzap. “Is this it?”
The brilliant figure nodded.
“So, we’re hearing a ghost on your sound system?”
“Actually, you’re talking to a ghost on his sound system,” said the speakers. “I can hear you, too.”
…
“I’m not talking. I’m just translating what he’s saying into radio waves so you can all hear—WHAT?!?” Zzzap looked at St. George, then Stealth, and then over at the corner of the room.

Excerpt From Ex-Communication, pg 201
Peter Clines
https://books.apple.com/us/book/ex-communication/id635706546