@Sunshine yes that's right. The issue lies with the Wi-Fi not the power line. I think you're right about the 2.4 ghz. I just bought a pair of Deco P9s which offer 5 ghz and it's working flawlessly.

The tpPLC app shows a data rate of ~ 395Mbps. It does vary depending on whether i plug it into wall socket directly or via a power bank - the 395Mbps is shown when connected directly. I can obtain...