[graf_von_anonym]

It didn't break "for no reason". You just don't know what the reason is, and, bar some educated guesses, nobody here can tell you.

What I can say is that illegal torrents tend to be more heavily used than legal ones. This extends to legal and illegal seeds. More use increases the odds of instability, and sees it shared across more users, which reduces speeds. Sometimes the weakness is in the protocol rather than the transport, and torrents, for all their supporters, are largely created by free clients that see little testing before release, often purport to generic compatibility but cannot guarantee it, and are often taxed by the use to which they are put even as they themselves tax the networks they run over. I have seen consumer routers and PCs collapse under the flood of connections opened by torrents, and its often upload that does it. It could be, indeed, I would say that it is probabilistically likely that that's what's happening. The act of resetting your modem and router also serves to interrupt these connection, and to reset the list of connections held open by your equipment.

Of course, you don't have to take my word for it. What I see as logic and reason may simply be Virgin Media's lies chopped into fine powder and cut into lines by Occam's Razor, drawn straight into my impressionable brain by the loyalons exuded from the co-axial snake.