Recently, I have been experiencing high latency (around 10k ms according to in-game diagnostics) when playing on a private server. But I get normal results when I ping test the server (~200ms). I have contacted my ISP regarding this matter and since the results from my speedtest is normal, they only assured me that "We will look into it".
The odd thing about all this is I have only experienced high ping on the private server. I checked my ping on other games; Dota 2, LoL, ESO, GTA V, and there are no issues. I also asked my friend who was using the same ISP as me but his ping on the private server is normal.
Troubleshooting methods I have tried:
1. Restarting modem. (Turn off/on)
2. Resetting modem. (Reset button)
3. Connecting via WiFi or LAN cable
4. Turning off Firewall
5. Turning off Anti-virus
6.Uninstall/Re-installing the game
7. Using a different PC
8. Assigning a DNS to my network driver
Ping test results on Google DNS:
https://drive.google.com/file/d/1Rh5wGFoIyFwZ3ZbOIxOIRw2k0zU3HHXC/view?usp=sharing
Ping test results to the private server.
https://drive.google.com/file/d/1mQHeYh0RpU6QOiDPmonqE13FCJkt0fhZ/view?usp=sharing
Edit: Sorry forgot to add. The game is a private server of Wow hosted by Warmane. Specifically the server Icecrown.