Walkie Talkie

Who and what is the dark voice coming through the walkie-talkie after an ouija board session?
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“Once he walked away, the walkie-talkie beeped and just kept letting out the static noise. What was stranger was that the channel had switched to 66.6. And through the static noise that we heard, we also heard a faint voice calling out to me and my brothers, it seemed, but as the static grew quieter, the faint voice began to speak clearly, and in a raspy gravelly voice, someone was saying goodbye three times before the signal went completely dead. We threw away the walkie-talkies and the Ouija board and never spoke about it to our parents.”