Listened to a Leslie Flint direct voice recording sometime last year
https://www.leslieflint.com/recordings-archive and there was mention from the spirit world back in the 60's that there would be communication devices in the future that would function in such a way where the spirit could communicate through such devices.
Whether the spirit box type of device is what was spoken about 60 years ago I haven't a clue but about 5 months ago a friend of mine tried this device and erik (of channeling erik) came through when I was not there. He has been through a few times to me before just saying hello and watching over our group when it was mentioned on the spirit box that erik wanted to say something to me.
The following week after our group the spirit box was used (I personally don't resonate with all the interference noise) I found it a little stressy but several sitters heard the words, I know it's difficult, and the words death and loss came up.
My dad passed over two weeks later, I had a thought in the back of my mind that it better not have something to do with him as he had recently not been that well.
Just thought I would share my only experience of this type of communication.
x daz x