This is typical for WiFi and where folk share an internet connection. Nothing wrong so far except that range extender. That builds in a set delay.
Try powerline if you can't get a direct line to the router.
Hi, recently I've been getting extremely frustrated with the fact that my ping on games such as League of Legends and Team Fortress 2 have risen to a constant 500ms+. This confuses me as I the pc I play on is about 5-6 feet away from my xfinity router/modem, through a ceiling. My current setup is an ethernet cable running into a netgear range extender, which is then connected to the wifi 5 feet away. People have told me using a PCI express network adapter would not help my problem. Is there anything I can do?

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