@Philbert The switch is unmanaged, and is connected to the main deco as it does not have enough Ethernet ports for my network. It's just to connect the one Deco with an Ethernet backlink and my...

I get 50Mbps down and 25Mbps up from my ISP. This morning, the download speed on my Deco network has slowed down to 100-200kb/s, while my upload speed has remained unchanged. This happens even over a...