Humming noise and strange behaviour during homing

[MatthiasWeiss 0]

Hello, ladies and gentlemen!
I'm not really new to 3D printing but until now I've been a silent reader.
At the moment I have a problem, which I hope I can solve with your swarm knowledge:

Recently, my Ultimaker 3 seems to have a problem with the limit switch. When it wants to zero the axes, it moves backwards normally and also reaches the limit switch. However, there is only a short buzzing noise afterwards and an error message is displayed that the end stop has not been reached.
As already mentioned, this is not true. In the diagnostic window, I can press all the end stops and they also appear. If I press the switch manually during homing, the same thing happens: The print head stops immediately and there is a short buzzing noise.
I have even installed a new limit switch and tested it by hand - with the same result. In the meantime, I was so desperate that I replaced the main board and did a factory reset. Unfortunately, all this did nothing.
Maybe someone has another idea?
Many thanks in advance!

[Mlke 0]

Hi, I have the same issue and no idea how to fix it...