I am experiencing frequent spiking every 11 minutes in gameplay during online games/matches.

I experience the spiking in two separate 3-5 second periods that occur back to back every 11 minutes or so while in online games/matches. I have began to record the time of the spiking occurring and have found that it is happening every 11 minutes. I have used the xfinity app to test the connection several times and each time it says I am getting around 110%+ of the 1200 mbps plan speed. However, when I intentionally tested the connection around the 11 minute mark a few times the speed to gateway dropped as low as 50% of the plan speed with a recommendation of restarting the gateway which I have already done multiple times. I instantly tested the connection again after the 11ish minute mark and it was back to the 110%+ range. I believe I was testing the connection when the spike/drop in mbps occurred. The speed and connection are fine as the xfinity app shows outside of this frequent small window of spiking/drop in mbps that lasts 3-5 seconds and occurs every 11 minutes. I have attempted to restart/reset my gaming console and gateway. I have tested online games/matches with a wired and wireless connection. I have tried using different consoles and devices. None of these potential solutions have solved the issue. I began to experience this issue around Wed 6/12.

Thanks.