I tried setting it to 0, -1 and blank value but it is always there, so i set it to some huge value and that also did not help, but it would be nice to have option to actually turn it off. I'm sure i got much better speed per upload before i limited it first time.
EDIT: it is working, problem is on WU and FSC side, i tried other filehosts and it works fast. Or maybe it is caused by connection from datacenter, etc., definitely not on your program side.