Random client crashes and severe ping spikes in-game

Hello,

I'm experiencing two issues while playing and I'm hoping you can help me track down the cause.

1. Random crashes to desktop
At random moments the game starts to stutter slightly, and within a few seconds I can already tell what's coming — the client closes itself and dumps me back to the desktop. There's no error message; it just shuts down.

2. Extreme ping spikes near bosses / certain actions
In specific locations, during boss fights, or on various random actions, my latency spikes dramatically. Networking jumps from a normal 30–40 ms up to around 12,000 ms. Once it reaches roughly 12,000–16,000 ms, the game crashes as well.

Important: this is not a problem with my internet connection. I checked my connection during these spikes and it was fine — the issue happens only in the game, not in anything else running at the same time.

Has anyone encountered problems like these, and is there anything I can do to fix them? I'm happy to provide any logs, dxdiag info, or my system specs if that would help with diagnostics.

Thanks in advance for your help.