I have a problem on all distos I've tried (Ubuntu, Manjaro, openSUSE etc.). It causes a strange noise when my speaker or headphones' audio starts playing. Anyway I know the solution: I have to type this command
$ echo 0 | sudo tee /sys/module/snd_hda_intel/parameters/power_save_controller &&...
It started working! I've added 2 kubuntu repo and shutted down PC. Now I opened back and I can see new icons, themes etc. Can you see it too? If you can't I'll tell you what I did.