My understanding is their network infrastructure is old and oversold, given the sudden rush to upgrade nodes/lines.
Very high chance it’s not your PC or network hardware. I’m been going through the same thing for since May also, so I have to ask, are you in FL?
When the internet is working correctly OBS suggests 1080p 60 at 6000 kb/s, when internet is running badly OBS suggests 480p 30 at 1800 kb/s.
Twitch Bandwidth Tool mirrors this as well, 8000 kb/s and 805+ quality to tested servers when good, 1000-3000 kb/s and 0 quality when bad.
The Cox specific speed tests will often show okay speeds because it runs once and that’s it, it doesn’t stay running.
I would say run OBS in “bandwidth test mode” at 6000 kb/s. Whatever kb/s it shows will be close to your actual upload is. I saw 3000 kb/s when tech was here, he saw 3mb directly at the pole, so isn’t my hardware.
If you see below 3000 kb/s upload that’s under the FCC broadband requirements, and filing a informal complaint will have Escalations calling you in 2-3 days. They actually do listen and try to fix the problem.
Sadly calling and emailing gets you non Cox techs who will speedrun the visit and not really do anything, as they are supposedly paid based on how many jobs per day. Out of 5 tech visits, it wasn’t until my complaint that I finally got someone competent to come out, and thankfully Escalations will give you their direct number for further problems.