@bdentino Try these settings, obviously you are not using PPPoE but the rest of the settings might work.

@dudeparebro Hi have you tried to set "Get IPv6 Address" to "non-address" and "DNS address" to "auto"?

@Wifi_Guy Sounds like a faulty cable to me then, 5e should easily handle 200mbps, could be a faulty connector on either end or a damaged cable. Best to replace.

@Wifi_Guy Also if the C6 has easymesh feature make sure that is switched off on the C6 web GUI as it can interfere with Deco in AP mode.

@Wifi_Guy Must be an issue with your ethernet cable to that Deco, if you move that Deco to right next to or near the C6 and try a different/shorter ethernet cable, then check you are connected to...

@kb867 eBay is good for used/new M5's. A single unit is about £50 to purchase, bidding normally ends up more than that. There are sets of 3 going on auction which normally end up going for about...