I'll open the Forum Sticky for you to add this if you wish.
Bob
Our Powerline adapters were giving us poor performance.
We discovered that cellphone charger cords plugged into power outlets in the same room with the powerline adapters were the cause.
The charging cords cause electrical interference which affects the powerline adapter's signal quality. Even if your cellphone or tablet isn't being charged the charger cord still seems to interfere with the powerline adapter.
So, unplug those charger cords even when not in use. It doesn't matter if they are the USB type or "wall wart" type your powerline network is better with them unplugged. We also leave our battery charger unplugged when not in use, although i can't confirm that it generates interference.
Our solution is to use a power outlet by the kitchen counter for charging phones and tablets.

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