@Bobster316  Hello, 

As you have multiple powerline units, it is recommended to download tpPLC Utility to monitor its Status. 

1. You could try to reserve an IP address on router for devices connected to powerline unit, and see if that help with stability. 
2. Turn off Power-saving mode on powerline devices：https://www.tp-link.com/support/faq/2018/
3. For test purpose,  it is recommend to test 2 powerline units at a time  (A->B, A->C, B->C). and see if the issue happens on certain unit or certain wall socket? 

May I know House Led/LED Status on both devices when AV600stops working ?Please check the IPv4 address and gateway and send us a photo: https://www.tp-link.com/support/faq/838/

Please ping the default gateway and send us the ping results：https://www.tp-link.com/support/faq/838/

May I know your network topology : eg: Router Archer C7 --PA4010  in living room <House powerline> WPA4220 in bedroom upstairs ? Do you have a stable wired connection on the main router?