I have an Airport Express connected to my modem (which provides 60 mbps download speed). The Airport Express is in DHCP + NAT mode, has one computer connected to it via Ethernet, and has other devices connected to it via Wi-Fi.
For some reason, when one device on the network is using a lot of download throughput to connect to the Internet (e.g., video streaming, downloading software updates, etc.), the other devices are unable to get more than minimal throughput to the Internet (e.g., simple webpages barely load). The device using a lot of throughput could be connected via Wi-Fi and even the computer connected via Ethernet will get little throughput.
Has anyone experienced this before and know how to ensure all devices have reasonable throughputs? I assume the issue is with the Airport Express. I have tried restarting the router along with reseting it and setting up the network again.