Fraction of a Mbps Even After Modem Swap

Hello!

My internet has been much slower than the my plan's speed for several weeks. The download is still good (probably faster than I need) but the upload makes internet browsing and file upload impossible.

A few weeks ago, my upload speed was usually around 0.2 Mbps, peaking at around 0.5 Mbps tested multiple times over multiple days with multiple devices, one including a laptop with an ethernet cable connection to the modem. Resets did not fix the speed. I used the XFinity app speed test and speedtest.net for the tests.

A few days ago, I called a technician who, after some data collection, claimed that the modem I was using had some firewall that was blocking the full potential of my plan and shipped me a new one.

I installed it and the upload is even worse on the new modem. I'm averaging less than .1 Mbps and peaking at about .2 Mbps. Resetting it does not help. It is not possible for me to upload video footage to my business partner with this speed, it stalls out.

What do I do? I did some poking around and I saw that maybe the commscope splitter may be limiting the upload but I do not want to mess with it until I know it's not something more obvious.

Thanks!