So I trying to upload a 970MB file (Thesis project) to WeTransfer (needed to send it to a group member) and it was uploading at around 0.02MB/s...left it running overnight and after about 20 hours, Firefox crashed before it could complete. Needless to say, I was fuming.
I thought it was my ISP that was the problem - speedtest.net was showing an upload speed fluctuating around .55mbps, which is still way faster than my upload at WeTransfer, but still well below what I should be getting. Then I tested on another computer and I got 2.0mbps!
Winds up it was the stupid Network iControl in the ASUS AI Suite II that was causing the problem. This build is only about a month old and I guess it was enabled by default when I had installed it. It's supposed to prioritize traffic, but obviously sucks at it. It was set on auto, where it should prioritize whatever is active. But just to test it, I created a profile that set Firefox to always be high priority and it was still only hovering around the .55mbps mark. So I turn it off completely, and voila....upload speed is back to normal and the 970MB file is about to finish up after just 30mins.
Curiously, download speed was not negatively impacted with it on, only the upload speed. Weird. But whatever, I have a fast enough connection - I don't need some stupid network monitor "prioritizing" traffic, so eff that shit.
So figured I'd post this as a warning to anyone else that may be using it - you may not even notice until you go to upload a big file.
tl;dr - ASUS AI Suite II Network iControl was "capping" my upload speed, so if you're using it, go test for yourself because it may be doing more harm than good!