I've been using this 3 unit mesh router for a year and half without issue. I recently changed my ISP from cable to fiber and about an hour after connecting to the fiber modem, the speeds dropped significantly (running speed test from the router app). Cable ISP was 1Gb/40Mb (always consistent) and the fiber ISP is 2Gb/2Gb. When the Deco was first connected, it was operating at the full speed, 2Gb up/down. After approximately 60-90 minutes the speeds dropped to below 50Mb each. QOS and MLO are disabled, IoT is enabled, no NAT. I have rebooted the modem, main router, and satellites several times with no change.

If I connect the Eero router that the fiber company supplied, I get 2Gb/2Gb consistently. Same modem, same ethernet cable. Also, if I reconnect my cable modem, I get the expected speeds (1Gb/40Mb) consistently.

Please help! My next step is to factory reset all three Deco units.