Hi. I have this router and a USB D-Link DWA-125 plugged on a Dell Inspiron 640M because the internal wifi is not strong enough so I disabled it already. The problem is that the wifi is going only at 72 Mbits/s when the usb itself is 150N and the router is 300N. Is it the WMM function that makes it or it could be another problem? I tried to change it of usb port and all the 4 ports are at 72 Mbits/s. Thank you.