DLink problem

I have currently two computers setup on a wireless D link to share my comcast cable. The connection seems fine on both computers but in the computer connected to port 1 on the router the download's seems to just stop and slowly to goes to zero. This never happened when my computer was connected directly to the modem. Only when I installed the router. I used dslreports.com and accesstimewarner.com to check my connection and the results was like before I installed the router. If the results are the same as before does this mean that maybe the bit torrent or kazaa is the one having the problems?