I googled A LOT and I think I found the solution to this problem. Open utorrent. Go to Options -> Preferences and apply the following settings:
1) In Bandwidth, set Global maximum number of connections to 200 and Maximum number of connected peers per torrent to 100.
2) In BitTorrent, disable DHT Network, DHT for new torrents, bandwidth management [uTP] and UDP tracker support.
3) In Queuing, set Maximum number active torrents to 2 and Maximum number of active torrents to 2.
Now shouldn't have any problems.
Disabling DHT and UDP tracker support doesn't seem to have much effect on download speed in our case. Because even after disabling them, I download with the speed of 350-450 kBps (provided that the quality is seeds is good).