does it stop after few sceonds ? If so it is normal. If not it can be something other. What is your Anti virus?
goto command prompt ant type "netstat" when this happens (close all the browsers, torrents and other internet using applications before you do this) and you will get a result. take a screen shot or copy paste the result and show us.
Not sure how technical you are, but if you installed a packet capturing application such as Wireshark, you would be able to see where the traffic is coming from (source IP address). You would then take this info and use WhoIs to see which orgination is using this IP.