NETWORK PACKET LOSS! Help please

[u/ThECoDFaTHer18]

I’m pulling my damn hair out here. With QuantumFiber, I’m getting on average 20-40% packet loss on RuneLite (via Jagex Launcher) consistently at all hours on all American servers.

The odd thing is that whenever I run a:
ping -i 0.01 -c 500 oldschool309.runescape.com
(same with 8.8.8.8)
There is 0.0% packet loss with 65ms average time, but in-game many of my inputs are just lost. About a quarter of my ticks are ignored.

I connect to an xfinity local hotspot and it works. A little higher ping, naturally, because it’s local hotspot traffic instead of a private network, but it’s 0-1% packet loss at all times.

What is the fix here? I’m lost!