I had Verizon in to fix internet problems and when they were done a speed test showed 500 Megabits per second between the router and Verizon, but only 25 megabits between the MacMini and the router. Verizon thought something was wrong with the Mac. What happened?
After the tech left, I fiddled around a bit and in the process moved a couple of USB hubs that had been sitting on the MacMini, the MacMini itself, and the router, which is only about 2 feet away from the MacMini. When I tried it again, the data rate from Mac to router jumped from 25 Mbits to 500 Megabits. A little digging found that MacMinis from 2012 to 2020 have their WiFi antennas on the bottom, so putting anything metallic on the top or around it can severely limit data rate. So I have two recommendations if you're dealing with slow data on a MacMini 2012-2020:
1) Check data rate with a speedtest that shows data rate both between the Mac and the router and the router and the carrier if you can find one. (Verizon has one at speedtest.verizon.com, but it may only work with Verizon routers.)
2) Don't stack things up on or around your MacMini, and try moving router and Mac to different positions to see if that helps.
After the tech left, I fiddled around a bit and in the process moved a couple of USB hubs that had been sitting on the MacMini, the MacMini itself, and the router, which is only about 2 feet away from the MacMini. When I tried it again, the data rate from Mac to router jumped from 25 Mbits to 500 Megabits. A little digging found that MacMinis from 2012 to 2020 have their WiFi antennas on the bottom, so putting anything metallic on the top or around it can severely limit data rate. So I have two recommendations if you're dealing with slow data on a MacMini 2012-2020:
1) Check data rate with a speedtest that shows data rate both between the Mac and the router and the router and the carrier if you can find one. (Verizon has one at speedtest.verizon.com, but it may only work with Verizon routers.)
2) Don't stack things up on or around your MacMini, and try moving router and Mac to different positions to see if that helps.
High speed USB cables, drives, displays and other devices can cause Wi-Fi and Bluetooth interference.
see > Resolve Wi-Fi and Bluetooth issues caused by wireless interference - Apple Support
The Mac mini's are more prone to weak reception than other Mac's because their antenna is built into the bottom cover.
I would,
make sure that there are no metal objects or appliances near or in-between the Mac Mini and Router.
move your USB cables and devices from in-between the Mac mini and router to see if that helps.
stand the Mac mini on it's side with the bottom facing towards the router to see if that helps.
Thanks for confirming what the problem was.
This will help prove to others, that high speed USB cable and device interference is real.
What makes wifi extremely slow on a 2018 MacMini
