Something else came to mind. Is the console connected to a computer and/or an AC power pack (you mentioned console batteries)? If yes then check your grounds to be sure your computer is grounded. Ungrounded power connections will cause many problems like this.
Yes, it is grounded. I had 25,5 m/s readings with the anemometer and when I put the computer grounded, the wrong readings were gone.
I was thinking that could the problem be in the electronics, like console capacitors?