I had problems with me losing internet connection - after a while I was just losing my internet connection (couldn't connect anywhere) even though I'm on broadband.

This was resolved when I reduced my number of simultaneous uploads - it was up at 20 and I reduced it down to 7. If you have a lot of other software (you maybe using other clients too?) then reduce it further. That might resolve the problem for you too.

At the end of the day, if it's 7 then some users have to wait a while but they'll get a faster transfer when they finally do because they won't be sharing it with so many other users.