Hoping y'all might be able to help as I cannot seem to get to the bottom of this.

About six months ago, I started to experience significant latency while gaming on WiFi (I know I know). To address this, I ran a cable and connected my PC directly to the router. This helped somewhat, but there was still a lot of latency, which I figured was due to packet loss. I used PingPlotter and even just trying to reach Google resulted in significant packet loss at times.

At that point, I figured it must be the modem - my modem was quite old and only had eight downstream channels and four upstream channels, which I figured just wasn't enough for the 30 devices I have on my home network. So I replaced the modem with a newer 24/8 model and the packet loss dropped significantly, which was great. I still occasionally get latency spikes, but I attribute this to my ISP (Optimum) and everyone working from home due to COVID.

So all was well, but a few days after switching out the modem, I started to lose my connection completely while gaming. This had never happened with the previous modem - the packet loss would cause huge latency spikes, but I never actually disconnected from the server. Looking at the logs for the new modem, I see a bunch of T3/T4 timeouts. When these occur, I have to unplug my modem and plug it back in in order for network to come back up.

Screenshots from my modem available here: https://imgur.com/a/CPXUVO2

I tried talking to my ISP, but they (of course), were useless. They basically just said "no issues on our end, we see your modem is successfully connected" and attributed any issues to the modem itself. There are unfortunately no other ISPs available in my area, which honestly is crazy because I live in Brooklyn, NY.

I've gone about as far as I can by myself, so I would appreciate any suggestions. Thanks!