New User PLW1000v2

powerline devices are sensitive to interference. If your pick a plug light is red, it means you have the worst connection. 

Amber is -decent and green is best connection. 

things that can influence powerline is: surge protectors, gfci outlets, arc fault breakers, high draw appliances, bad/cheap cell phone chargers, old wiring, and electronics poorly designed that are feeding back into the wiring system.

You can optimize powerline device. here's an article with a few tips.

https://www.pcworld.com/article/3041996/pump-up-your-powerline-how-to-get-the-best-performance-from-a-homeplug-network.html