External HDD not showing up when connected through usb 3.0 port

I have a g5 250 hp on mojave 10.14.3. Everything works great, except from external usb disks. When I plug them to the usb 3.0 port they don't show up in disk utility (although I can hear them spin + the activity light is on) but they work perfectly when I plug them on a usb 2.0 port. I should note that the usb 3 port works perfectly with usb 3.0 sticks (and I get 3.0 speeds). I use the UsbInjectAll.kext