Peers dont download from me always

[AndersMalmgren]

Ok, so my ratio have gone down since I moved to qBittorrent from uTorrent. I have disabled UPnP and are using a fixed port for incoming connections which is forwarded (both UDP and TCP) in my router to the server machine hosting qBittorrent.

I can see alot of peers connecting but they disconnect right away again. Also some peers are connected but do not download anything from me. The guy from turkey in this screen shot has been connected since I started monerting this specific torrent without downloading anything. The swede just connected and then was disconnected a second later. I use 3.3.16 x64

[Seeker2]

Almost certainly related:
Not connecting to some peers #7155

Even when it works, it's often very slow uploading:
#4284 (comment)
(Applies to internet speeds >1 MB/sec even if not over a LAN!)

If it uploads really quickly, qBitTorrent and Deluge can crash if a large cache size is used:
Crash if upload is high...15-30mb per sec. #6594