Finally I fixed the problem with my Cerbo and wifi connection which was bugging me for weeks.
It started with Gui getting really slugish. Found out, it was flooding the wifi channel on my router, until I re-started the router channels, but it started to flood the wifi again. I don't know how the cerbo is programmed to open server connection, write data and close connection, but I have seen this before where software opened and closed a connection to the server for every single line of data, and with poor connection, the queu got longer and longer and took up all the cpu power. However, another considerable problem was the wifi in the Cerbo. Re-arranged the antenna's in the cerbo, but this did not solve the problem. I thought, lets go another route. Checked which antenna in the cerbo was for the wifi 2.4, removed it, and replaced it by an external antenna. Very cheap and efective solution with minimal impact on the cerbo. Just one 6 mm hole in the housing.
Cerbo has been running 100% since. No more wifi flooding or horrible lag on cerbo gui.
And signal on cerbo, see for yourself.