I'll have to start this story a little further back: Before I had tixati I used utorrent. I have two computers in my house connected to the same router and on the downstairs computer it didn't matter how much I was downloading/uploading, it could be at full bandwidth and web browsing would be completely unaffected, while on the upstairs computer as soon as I started utorrent, it didn't matter if nothing was uploading/downloading, I would be completely unable to browse the internet, and it would stay that way even 5 minutes or so after I closed utorrent.

So I finally got fed up with utorrent and switched to tixati and everything was fine for a while, I could browse normally while downloading/upping but now some troubles have started. It either happens that after I start tixati, again, even if there's nothing actually downloading/uploading (there are active torrents, but no transfers) the web browsing becomes very slow or impossible, OR, this morning, the browser (firefox) downloads pages relatively quickly, but it takes it a while to get started after I click on a link.

The difference is that with tixati things go back to normal immediately after I close it, unlike with utorrent where it took a few minutes for things to go back to normal.

Does anyone know why these things happen?

is your bandwidth throttle set?

It isn't, but I figure (not that I know anything) that that can't be the issue because sometimes browsing can slow down even if there is nothing being transferred (there are active torrents in my seeding list, but no one is leeching off me).

And yesterday, after I'd written what I did in my original post, I had the experience that I was downloading and uploading with tixati at full speed and yet browsing was working perfectly, as if tixati was closed. And now I find that it varies like that. Sometimes tixati being open will impact the browsing (and in different ways) and sometimes it won't, regardless of whether I'm leeching and/or seeding at full capacity or not.

I am assuming this is fixed now that you have your ports forwarded correctly? But if not are you on DSL or other phone line and using a router and modem?

Sailor, it's not resolved itself since I forwarded the port.

You're right, I'm using ADSL and a router (no separate modem).

I don't understand? What plugs into your telephone line? Routers are not usually modems and only have a Ethernet cable out, it must go somewhere to connect to the telephone line.

It has a modem built in and goes into the phone line. It's a Chinese shoddy brand, ZTE ZXV10 H108B.

I think I see where your problem might be. I searched the model number and found many posts and descriptions on how to set it up correctly. This usually means other people are having problems. It is likely something in the modem section not being compatible with your ISP. The thing I would suggest is to call your ISP support while in the modem screen and go through all of the settings.
One little mistake can cause problems, for instance if IVP6 is enabled or set wrong. If that is enabled on yours you may first want to disable and see if that improves it but likely the only way to resolve this will be a call to your ISP support.

Thanks, I'll look into that.