@IwanvB ...I also see the system log files, almost logging issue/messages very second. Below a small snapshot....might there be a relation? Is this normal? (changed some of the MAC-addresses manual...

@IwanvB My switch is a Cisco SE2800 (8 port gigaswitch). And yes, internet (Wifi) remains working in the Deco, this means the connection from the ISP is stable. When everyting is connected straight...

Recently I have installed the Deco M4 in star-network. (Modem --> Deco base station --> switch --> Deco stations). I essence it all works fine and I'm happy with the wifi. But my switch keeps going...