Internet Routing/Latency Issue to Spain — Need Network Escalation

I’m having an ongoing problem with my Xfinity Internet connection and need help getting it to the right technical team.

We were not having these problems before Xfinity sent us a new modem. The new modem did not work properly, and after several tests Xfinity agreed that we should return it and reconnect our original modem. Since going back to the original modem, we have been having connection problems.

My husband has run several tests from the same computer, and the results appear to show that this is not a Wi-Fi, modem, speed, or bandwidth issue.

The connection is normal inside the Xfinity network, with latency around 25–35 ms. However, when the route reaches the handoff toward Orange/OpenTransit, latency jumps to approximately 160–181 ms, with packet loss and occasional spikes up to about 250 ms. The route toward 1&1/IONOS also shows elevated latency of approximately 138–149 ms, with spikes around 187 ms.

Our remote desktop connection to Madrid is now approximately 161–165 ms with dropped frames, both over Ethernet and Wi-Fi. On October 1, the same connection was approximately 109 ms.

Most importantly, when the exact same computer connects through Xfinity Mobile at the same time, the same Madrid connection is approximately 105 ms with no packet loss. The problem only occurs through our wired Xfinity Internet connection.

Our download and upload speeds are normal at approximately 711 Mbps download and 108 Mbps upload.

I have the complete traceroute results and IP addresses available, but I am not posting our personal connection information publicly.

I’m not very familiar with the technical terminology, so if someone is available who can assist my husband in Spanish, I would really appreciate it.

Could an Xfinity representative please help me get this escalated to the appropriate network/routing team and contact me privately so I can provide the complete technical information? I would also like a ticket or reference number for the issue.