I'm running a Minecraft server at my house on my laptop that is wirelessly connected to my router. It is a very small server (1-3 players connected at one time), but when a player connects to my server, my ping in League of Legends on my desktop will spike up from ~105ms to ~300ms for 3-6 seconds then drop back down to normal (~105ms). I have a 25 Mbps connection and am using an ASUS RT-AC87U router. With this router, I'm looking at my bandwidth and seeing no spikes in Mbps being used by my laptop.
This only started happening a few days ago and I'm not sure what would have changed. Any suggestions on what I could check?
Also, one user specifically connects to my server and the ping does not go back to normal after spiking up. It seems to stay at a steady ~130ms ping until she starts running where it spikes to over 200ms. I'm not sure what can be causing ONE person to do this. I have tested and made sure it was only happening with this one person.