I stopped using Minecraft for a long time now I started again, on German servers I still had a hammer ping but on English or American servers I no longer had a good ping. I have a freeze frame every 10 seconds. My brother plays a room above me and everything goes perfectly with him. Hope someone can help me!
Maybe use a Wi-Fi repeater. Can you play normally when he's not playing?
So we have a repeater at the bottom, then we have a small piece in a socket in our rooms where the piece connects to the repeater, then we make our internet cable in the piece and then in our PC
Well you have to imagine that the repeater shares the internet. So maybe I would only recommend a repeater. At best at the top or on the middle floor
(when the rooter is in the living room)
We have a router in the living room and hold a repeater in every room
Yes, as I said, just use a repeater. And try whether it should be at the top or on the middle floor. And then please access the Internet via WLAN. If you want to have the best Internet then you don't want to connect the LAN cable directly to the repeater but to the router.
Because your internet is so bad