For some time I have been putting up with erratic and slow VDSL. I have installed a Draytek Modem, which comes Down at 36Mbps and Up at 7.3Mbps. This is in the basement, and has a new Switch plugged into it. The switch is plugged into an adaptor in a mains wall socket. Two laptops are plugged into the switch as well. The performance on the laptops is the same as from the Modem. Upstairs there is a new TP-Link TL-WR1043ND Wireless Router plugged into a mains socket.
The strange thing is that the TP Router is only producing about 9Mbps Down, and 7 Mbps Up. Even stranger, the Computers upstairs are performing well despite the low readings. I tried moving the TP down stairs plugged into the Draytek modem and got the same odd result, thus eliminating wiring problems. Qes? is disabled, no difference.