Did you have to use http://www.danieltufvesson.com/makeresolvedeb ? I found the entire installation process on Ubuntu a bit of a pain (even though it did work) - I think the instability on my system is probably as a result of the rather convoluted installation steps.
When I use Linux for Audio and Video I DON'T update the computer and I don't have anything else really on that image. I use a second image for non-Audio/Video production. I did the same thing with Windows for decades.