“An unexpected disconnection occurred” in maps – instance crashes linked to CRIT asset/shader errors

I’m getting frequent “Abnormal disconnect: An unexpected disconnection occurred.” while mapping. It is repeatable for me across multiple maps and sessions, often triggered during combat when certain mechanics/mobs activate. My friends (same party/maps) usually do not disconnect.

This does not look like a network/ISP issue: I’m on wired Ethernet (1 Gbit), tried multiple gateways, changed DNS, disabled EEE, etc. Ping to an instance IP (example: 67.58.99.71) is stable with no packet loss (35–42ms). The disconnects are map-instance specific and often happen at the moment a certain mechanic activates.

Hardware/Platform:

PC (Steam)

GPU: NVIDIA GeForce RTX 2080 Ti

OS: Windows

Connection: Wired Ethernet

Renderers tested: Vulkan, DirectX 12, DirectX 11 (DX11 seems more stable but has severe performance stutter / not playable so not tested well)

What happens:

While in a map, during active combat (mobs attacking / mechanic triggers), I get kicked with:
Abnormal disconnect: An unexpected disconnection occurred.

The map/instance progress is lost. Seems to happen especially on abyss? But I'm actually not so confident.

Evidence from Client.txt (key patterns)

A) Vaal Shapeshifter morph CRIT errors preceding the disconnect (content/animation rig issue)
Multiple times, while mapping, Client.txt logs CRIT errors during morphing from:
Metadata/Monsters/VaalMonsters/Living/VaalCasterLivingShapeshifter.ao
to
Metadata/Monsters/VaalMonsters/Living/VaalShapeshifterJaguar.ao

Example log lines:

Manual mapping size mismatch (expected 90, have 107) when morphing ...

many lines like: Invalid source bone phys_... in manual mapping when morphing ...

Shortly after these CRIT lines, the instance disconnects with “unexpected disconnection”.

Maps where I saw this include (examples from logs):

MapVaalVault

MapHive
(possibly others)

B) DX12 render/shader pipeline related CRIT in another case
In one session on DX12, I saw CRIT render/pipeline messages related to a specific particle/effect asset, followed by the same unexpected disconnect (instance loss). (I can attach the relevant Client.txt excerpt.)

C) Sometimes the disconnect happens without visible CRIT right before
In some cases, the log just shows normal instance connect + map generation, then abruptly:
Abnormal disconnect: An unexpected disconnection occurred.
No timeout/fail-to-connect lines. This still correlates with combat/mechanic trigger timing in-game.



Troubleshooting already attempted (no improvement)

Changed gateways/servers

Changed DNS (Cloudflare/Google)

Disabled Energy Efficient Ethernet / NIC power saving

Updated NVIDIA drivers

Tried Vulkan and DX12; DX11 seems stable but is extremely stuttery and not playable on my system

NVIDIA Control Panel tuning + cleared NVIDIA shader caches (DXCache/GLCache)

Ping test to instance IP (example 67.58.99.71): stable 35–42ms, no packet loss.



Reproduction notes (as close as I can provide)

Occurs during mapping, not in hideout/town.

Often happens when a specific mechanic/mob activates while I’m being attacked (repeatable in similar situations like in abyss maps).

Vaal Shapeshifter morph appears to be a strong trigger (CRIT mapping size mismatch + invalid bones).

When it triggers, the instance eventually dies and I get the unexpected disconnection. This even affects all party members when they play with me. Kicks all of us out. This never happens for them when they play individually and separately. It happens when I play alone too, so not connected to party play.