After 14 months of a perfect 25 down, 5 up residential package with Comcast, since this past June, my upload has been showing similar results to what y'all are speaking of, and Comcast is giving me the same bullshit runaround. Even after corporate increased my package to the "blast" 80 down, 10 up, I'm still seeing inconsistencies pop up for a number of hours and then disappear and be completely fine for a while. It's making it impossible for me to stream to Twitch on a schedule.
I'm not nearly as learned as you two are, testing using those various programs and such, but I know there's an issue and Comcast is apparently clueless. Is there any chance anyone here'd be willing to help me figure out how I can prove to Comcast there is a problem with my upload still? Download is completely fine. I mean, even SpeedTest is showing me inconsistent upload speeds, but Comcast won't bite. All I want is a constant 5Mbps upload connection... I don't see why, for $70 a month, that's so difficult in this day and age.
I've only recently found this site, so I only have about 24 hours worth of testing to show, but it still shows huge variations in upload for chunks of time. Also, before finding this site, I was testing to Twitch servers around the US when I'd start dropping frames due to the poor upload, and I was able to see speeds varying from failing to connect to 100Kbps to 3.2Mbps. See attached screenshots.
Thanks for any feedback...