Exactly the same issue as Sugarfoxx. Has been getting more and more regular for the past year or so, to the point now where it's almost unplayable.
Only one instance crashes at once (crashes also when just one instance is active) doesn't matter what graphics settings are being used.
Processor Intel(R) Core(TM) i9-10900K CPU @ 3.70GHz 3.70 GHz
Installed RAM 32.0 GB
System type Windows 11 Home (version 22H2) 64-bit operating system, x64-based processor
Pen and touch No pen or touch input is available for this display
GPU NVIDIA GeForce RTX 3070
VRAM 8043 MB
Running normal live client
This has been happening to me for around a year, getting more and more frequent. I rarely go 30mins now without a crash.
Pretty sure I have tried all "fixes" mentioned in other threads, including full reinstall of Wurm and Java.