The MOCA/Ethernet bridge works both ways...traffic on the Ethernet segment connected to the Roamio will go over to coax, but so will traffic on the coax pass over to the Ethernet. Sounds like there was something coming in on the coax, which then passed through the Roamio to the Ethernet and that was causing some issue in your router that slowed it to a crawl. Glad you have it working properly!
Current Setup: 2 Roamio Pros, 5 Minis on FiOS (all with lifetime)
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