I finally got around to installing 15.5 on my main machine here (up from 15.0) and with all such changes there are bumps along the way. The latest was trying to get VirtualBox to recognize USB items. I went through all the known and suggested fixes, the obvious ones like permissions and group memberships, etc but absolutely nothing was making a difference, to the point I started thinking "bug". So, I tossed a hail mary <-- American football term - and downloaded the .rpm from Oracle and told it to install and overwrite all. It did and the USB problem disappeared. Bug squished. The VB version on the OS repositories sucks. I have arrived at 15.5 late in the game; everyone else was probably aware of this item but thought I would put it out to the group anyway, just in case someone may have missed it.