if your with Virgin i know they 1/4 it every hr for 4 hrs...
trust me its a pain in da backside..
i use Utorrent, but check to see if your program cycles ports on start up? if it does, make sure your using a port range your router has open. (and isp) i'd suggest sticking around the 4000 6000 mark. UDP AND TCP. a good test to find out if its your router or ISP is to bypass the router completely. connect direct to modem.. or if your cleaver, open your router, there is an option that puts you outside the network cluster. Dax or somethin, i cant remember what its called. its close to the NAT options on mine. dont leave it off as it reduces your security massively.
also, i donno how new to torrents you are, but are u getting a good seed/leach ratio?
also if your using somethin like IPtorrents, u have to have a fair share ratio to get a good bandwith.
food for thought