Correction: It does not buzz in standby mode, but when the power supply is still active until the appliance switches off after 5 minutes.

I have been using the device for two months. I have only rarely noticed the buzzing. Probably because I have replaced the German plug with a CH angled plug with a built-in switch (manufacturer: Steffen). As soon as the water has reached the desired temperature, I switch off the cooker using the switch so as not to waste any "grey energy". That's why I don't hear any humming while the appliance maintains the set temperature by reheating. It is true that the cooking noise in this cooker is slightly louder than a Bosch cooker at work. For me, it doesn't really matter.

Not this problem but only 50-70-80° and Warm but not 90° as on the presentation!!!!

The model is a gimmick. Already too heavy when empty. Technical gimmick is not usable.
Too loud in boiling water. Very heavy with water. Not suitable for children and older people. Danger of accident.
The idea is good but the execution is very poor.

No, not normal!