I have a DIR-628. My main PC is hardwired to it and my laptop uses wireless. I did not experience this issue before but now it has shown its ugly head.
My download speed has dropped from a blazing 10mbps-16mbps down to a 1.5mbps-2.0mbps.
I have unplugged the router and the issue is cured. I get what I am paying for. However, when I plug it back in I get the same negative results.
Loss of download speed.
Looking for help. Very much a novice at networks.