I've noticed for the past few months, when turning on my PC and waking up powerlines from sleep mode.  Doing a morning latency ping test to 8.8.8.8 shows a 3x latency increase than normal when connected via ethernet to powerlines.  Testing router itself shows a stable result for latency, indicating the issue lies between my ethernet powerline adapters.

I've found the only way to fix this, is either doing a manual repair of both units or using TP-PLC app (on Windows) and performing "Secure" action which resolves this issue temporally until either next morning or even during day.

I've had replacement of powerline adapters (so now using latest hardware revision of powerline adapters) and strangely still encountering this issue.

I've now been suggested to use the "PLC to VDSL" mode (lowering my powerlines capabilities) by senior engineers, but this doesn't sadly explain what could be causing this issue, nor why I didn't experience it before a few months back.  I'm only have 2 powerline adapters connected to home writing too.

If anyone has suggestions about what could be causing this regular occurance, I'd greatly appreciate your guidance and views.