The connection/drive shaft of the brew unit inside the coffee machine is not sufficiently lubricated.
Lubricate the connection/drive shaft of the brew unit with silicone grease.
You can order the silicone grease in the Miele online shop in the “Appliance cleaning and care products” section under “silicone grease” or via Miele Service, “silicone grease material number 05132001.”
Consult the operating instructions for further information.