Hello,  My Roon Nucleus+ is hardwired with cat 8 from my Verizon Modem.  I am then hardwired to two Roon endpoints.
I use a separate linear power supply for the Nucleus set to output 19v.
There is an internal hard drive installed and NAS connected.
Everything sounds great.

But my Nucleus+ is crashing now two or three times a day (becomes non responsive and my remotes can not find it.

I have tried rebooting the remotes, the endpoints and the router with no effect.

I must power off and back on the Nucleus for it to be ready and seen again.

Any help or thoughts appreciated!
Reading this thread, it’s always a reminder of how easy it is to pop a CD in a tray and hit “play”
Roon support should turn on diag to isolate the issue.
I had a similar issue and diag showed the SSD was up but logging errors, a new SSD corrected the issue.

Roon support was slow to respond but accurate. Once diagnosed I was sent a shipping label, 7 days after shipment it was returned to me with a fully functional SSD.

It was under full warranty, beyond time my cost was zero.

^THIS^  Roon diagnostics is the direct route to an answer.  Roon 1.8 would not cause only your Nucleus to crash.  Mine was an M2 drive problem as well.  I could have guessed and fiddled instead, but Roon support found the problem.
Thanks again to all...I am waiting for the next crash to alert ROON so they can investigate.

Of course it has been flawless since I contacted them!