BitTorrent Kills my Internet even when not torrenting/active

[Kyro]

For some unknown reason after installing BitTorrent; my broadband speed has been drastically reduced even though:

1) I am not torrenting anything

2) I am not running BitTorrent

My download speed drops from around 10Mbps to around 0.5Mbps although upload speeds remain similar.

I am sure BitTorrent is the cause of it because I've tried installing and re-installing a few times just to test its effect on my internet. Only a complete uninstall where the settings are removed as well seems to return my broadband to normal.

Can someone please explain to me why this is happening? Thank you very much.

[Harold Feit]

If BitTorrent isn't running, it's outright not the cause of your problems.

[Kyro]

You are certain it does not change any internet-related settings upon installation?

[Harold Feit]

I am.

[Doc]

I ran into similar problems with Bittorrent and Utorrent and found the problem to be my router.

It also choked all other Internet access.

Restarting my router cleared the many connections which had been opened for the torrent client but had not been closed properly, thus choking the router. I ended up with another router (Of all things, my VONAGE interface is now my main router - it han handle a shitload of siultaneous connections, I haven't been able to choke it yet) which could handle more simultaneous connections. I also limted the number of simultaneous connections in the torrent client setup, and this seemed to solve the issue. Maybe it will help you.

The Verizon FiOS routers are known to have this problem.

Some DLink routers also.