Lag spikes and Latency Issues

Hello, I have been with Xfinity for a little over a year. My connection in regards to gaming, online meetings, and streaming have all been fantastic, until this past August. Recently, on all platforms, I have been experiencing major latency/ping issues most notably during online gaming. I have looked into input lag through the Elite series controllers and used a wired connection, used multiple tvs and HDMI cables, moved my platform next to the router, used an Ethernet cable, Port forwarded my Xbox to servers of interest, and of course reset the modem many times. This problem does not occur at other non-local residences. I do not know if it is a node issue, but it is most definitely an issue outside of my home. Any information would be greatly appreciated, however I believe that other potential ISPs may resolve the issue.