Network Huge ping with Home Assistant connected to network

I notice that any of the computers in my network experience long response times while accessing the Internet (when my sons play a game they come to me with complaints about their ping-time)

I started a ping -t to www.nu.nl on another computer in my network which I’m referring to now.

Ping statistics for www.nu.nl
Packets: Sent = 50, Received = 50, Lost = 0 (0% loss)
Approximate round trip times in milliseconds:
Minimum = 54, Maximum = 7864, Average = 659