plasma-desktop sucking up 97,5 % of CPU

Everything appears to be running fine, but after a few minutes CPU usage start to increase and the task bar freezes. However the windows that are open keep running normally, I can type into them, move them or close them.If I happen to have the System Monitor window opened I can see that plasma-desktop is taking between 50 and 97,5 % of CPU resources, increasingly as I close other running processes and keeping my CPU maxed out at 100%
I don’t have any crazy apps or widget running. Just plasma-desktop, baloo, the other process are less than 0,3 %
Also, it will freeze instantly when I plug in a usb flash drive or try to mount a hdd.
Any idea how to fix that problem?

I did try reinstalling all the plasma-desktop related packages in synaptic, but the problem remains the same…

Did you deactivated the desktop effects for a test ?
Otherwise I am not sure what might cause that issue.

I did, it made a complete mess.

I belive I will reinstall, now since this 14.2 version will soon become unsuported, would it be a good idea to install the new rolling distro that just came out, and will I lose my home folder?

14.x will be supported until 2019 as it is based on Kubuntu 14.04 LTS.
As for the rolling it will most likely not take all your KDE SC 4.14 config into account as plasma 5 uses new configuration directories and in some rare occasions also config syntax for it. So basically you need to copy them older to the .config directory yourself.

14.x will be supported through kubuntu backports updates until 2019, from netrunner side until 2016.

In other words, no more support for that distro from this forum after next spring?

Of course forums support here will be always possible…