Without knowing I made a quasi-blind experiment. Suddenly I couldn’t sleep any more at night. The “three cups of coffee” feeling was back that I experienced before I had connected the metalworks in the basement with wires, resistors and pieces of shungite. After about three nights of bad sleep I had a look in the basement and realized, that both pieces of shungite had fallen down. They had been attached with tape and the glue had degraded. I reatached them and now I sleep well again. It really seems like the shungite attached to the side of the wire makes all the difference.