[SOLVED] Rather specific internet issue

[Brilliant27]

Almost every night my internet slows down completely after 7:00 pm, although it only effects my computer (Its not directly connected to the modem but uses a powerline connection).

 

[rgd1101]

sound like someone using something that interfere with powerline

 

[Ralston18]

And I will ask about the router: make and model?

The router's logs (if available and enabled) may provide some clue.

Who has full admin rights to the router? You will need help from that person.