PLC is first line?

[hydr]

Hi, try the devices (PLC) directly wall socket. If you operate the PLC via power strips, the throughput drops rapidly, as it is with line filters or isolation transformers !!

5 of the Phantoms are hard-wired through the wall and mounted with Gecko. The remaining Phantoms are connected to sockets, but they are on 3 different circuits. The same circuit as the Dialog is the one performing the best. I think its the back and forth between Wifi and PLC that really is causing most of the issue. 

I looked up line filter and isolation transformer, what are some common products these are in? I have not installed anything like this myself, but is it possible that the electricity company installed something like when the apartment was built?

Hi, no, this is not installed! For example, filter socket strips (Isotek, Supra etc) are meant! It is true, they are different circuits, but always the same phase!
On which fuses (Nr) are the phantoms connected?

Another problem with the PLC is fault protection (FI), which disturb the transmission in the high frequency range. And that is your problem! With you combi fuses are installed (ABB DS202CM), FI switch and fuse in one unit!

Hello,
Sorry for late reply, I have been sick with the flu the last few days. 

Wow, thank you very much! This is new information for me, and could explain why I am having such issues. #9 has 4 Phantoms and Dialog. #7 has 1 Phantom and #8 has two Phantoms. Would I have to replace the ABB DS202CM with a separate fuse and FI to solve this you think?

Thank you again for helping me, you have provided more help than devialet support have in over 60 e-mails back and forth, and endless testing.