Virtualbox 5.1.(12) Stability

[Ksmith]

I've been very disappointed in the stability of the latest virtualbox 5.1.2.. I loaded it on a beefy Opteron Octa-core and my Windows desktop (i5) at work. On the former I get random crashes and hangs of various Linux guests and a Windows 7 instance. And the same behavior on the latter. Running remote syslog'ing doesn't show anything wierd until the vm just spontaneously reboots. Has anyone else noticed anything similar? I've tried tweaking various settings to no avail. This is more of a note, as I am rolling back to 4.3 on the Opteron box, 5.x has not been the most stable since I put it on there, not to mention the graphics issues unless you downgrade the tools. I'm thinking of dropping back to 5.0.x at work, it's really depressing, because the 4 series was like a rock, and I depend on my debian (jessie) VM at my office to do various network management tasks from my desktop.

Anyone else notice a major stability problem with the latest?

[socratis]

1. This post does not belong to the "Suggestions" forum. It doesn't actually suggest anything. Moving to "Using VirtualBox".
2. Unless you expect "Me too... I think" answers, your question/analysis is too broad. Instabilities? Where?
3. Except some audio issues in 5.1.x series (which were addresses - partially in 5.1.12) there haven't been any negative brouhahas.
4. If you depend on something (your Debian VM) and it works (with 4.x), you do not update it, unless you first run some tests.
5. If you're getting "instabilities" (define?) with your guests, then pick a single (your favorite) guest and follow the instructions:
   1. Start the VM. Not from a saved or paused state. Clean start.
   2. Take the steps required to generate/observe the error. Record the error message. EXACTLY. Post a screenshot if you have to.
   3. Shut down the VM (if it hasn't aborted by itself). Not saved, not paused. Completely shut down. If you can't shut it down by normal means, close the VM window and select "Power off".
   4. Right-click on the VM in the VirtualBox Manager. Select "Show Log..."
   5. Save it (just the first log), ZIP it and attach it in your response (see the "Upload attachment" tab below the reply form).
   I would also like to see the "recipe" of the VM, the ".vbox" file:
   1. Right-click on the VM in the VirtualBox Manager. Select "Show in Finder/Explorer/Whatever".
   2. ZIP the selected ".vbox" file and attach it in your response.