The monitor is throwing noise down the AC line. Either change the monitor or try line filters.
Example: https://www.smallnetbuilder.com/lanwan/lanwan-howto/31316-slow-homeplug-try-a-powerline-filter
Hey there, whenever I switch off my monitor my network connection increases to over 25 Mb/sec, however, when I turn it back on it goes down to ~5 Mb/sec. (I was testing the connection speed in both conditions).
This made me confused because I thought the monitor has nothing to do with the internet.
(I'm connected through electricity (2 power lines)).
Thank you for your time!

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