Basically exactly what the title says... for some reason I still can't figure out, all of my torrents suddenly stopped working the other night. No uploading, no downloading. Tried a million different things to try to get things working again, and finally figured out that everything went back to normal (or even better than normal – my speeds seemed faster) if I just forwarded the ports on my router.

But then I switch on my VPN and everything suddenly comes to a halt again. Not quite as bad as before, but almost. I'm getting extremely low upload and download speeds. Zero peers on the majority of my torrents (stuff that had dozens of peers 2 days ago and shows dozens of peers on the tracker). Apparently my VPN provider doesn't allow port forwarding, which I guess explains it.

But I'm still at a loss as to what happened in the first place! (and how I'm supposed to fix it without forwarding my ports)