I'm trying to get 4 Wifi adapters running off the Pi (overkill I know), the adapter in question is the Alfa Network AWUS036NHA, the Pi runs smoothly and reads the adapters as I plug them in one by one until I plug the 4th one in and most/all of the USBs ports stop being read (sometimes few USBs are left working but it requires a reboot for them all to work again). I initially figured it to be a power issue (each unit seems to be 2W from what i've seen above) but when using an externally powered USB hub (https://www.robotshop.com/uk/7-port-usb-hub-raspberry-pi.html) I face the same issue... no matter what combination I use (ex. powering 2 adapters on the hub and 2 on the Pi). A second Pi 3 B+ that i have has been doing the same. Another solution I have tried is using 5V 5A supply and the only difference is that the 3 other adapters still stay on when the 4th is plugged in occasionally. Any possible ideas would be appreciated.