coppit

I'm not sure. Sometimes it takes nearly a day to show itself, and I didn't run it long enough in safe mode to know.
 
Here's what I think is happening... Hardware issues are causing segfaults, which cause some component of the web UI to fail, which then causes the browser timeouts. So basically not an UNRAID problem.
 
So given the instabilities of the recent Intel CPUs, yesterday I replaced my motherboard and CPU with an AMD setup. So far no GUI hangs, but I see these in the syslog:
 
Feb 7 00:19:32 storage kernel: ccextractor[528241]: segfault at 0 ip 000014d9771f2384 sp 00007fff1fd35308 error 4 in libc.so.6[14d977193000+195000] likely on CPU 9 (core 9, socket 0) Feb 7 00:19:32 storage kernel: Code: 5d c3 0f 1f 40 00 8b 47 04 83 e2 cf 8d 48 01 89 4f 04 89 13 eb bb e8 bb 9e 00 00 eb 92 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa <8b> 17 f6 47 74 80 74 74 89 d0 25 00 80 00 00 75 6b 55 53 48 89 fb Feb 7 00:22:55 storage kernel: ccextractor[543229]: segfault at 0 ip 000015540a56c384 sp 00007ffc97191298 error 4 in libc.so.6[15540a50d000+195000] likely on CPU 11 (core 11, socket 0) Feb 7 00:22:55 storage kernel: Code: 5d c3 0f 1f 40 00 8b 47 04 83 e2 cf 8d 48 01 89 4f 04 89 13 eb bb e8 bb 9e 00 00 eb 92 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa <8b> 17 f6 47 74 80 74 74 89 d0 25 00 80 00 00 75 6b 55 53 48 89 fb  
But it looks like a known issue with Plex or some other subtitle app.
 
We'll see how things hold up after a few days, but it looks like I'm in the clear. Thanks for all the help!

Okay, finally a breakthrough. The server hanged in the BIOS bootup screen.
 
My theory is that there is a problem with my hyperthreaded CPU cores 0-15. 16-31 are allocated to my VMs. The lower cores are used by docker and UNRAID. Disabling docker basically idles those cores since UNRAID doesn't use much CPU, which is why things are stable in that configuration.
 
I'm going to try disabling hyperthreading to see if that helps. I might have to replace the CPU. Or maybe the motherboard. Ugh.
 
Since my CPU temps never go above 41C even under load, I don't think it's overheating.