I have an additional monitor to which I connect via HDMI, it has built-in speakers, so I set audio to work via HDMI.
HDMI audio is working for System notifications like Login or Logout, which I enabled in KDE Workspace.
However I cannot get it to work for sound in general like music, or listening to audio in courses.
I bumped up preferences to HDMI in System Settings -> Multimedia -> Audio and Video Settings -> Audio Playback -> Device Preference, under that all preferences are set to HDMI in first place.
Backend is Phonon VLC, when set to Gstreamer it was worse, no sound at all.
Yesterday I plugged an audio cable from laptop to monitor and set audio input to audio in, speakers worked.
After rebooting today all sound was gone until I bumped up preferences as above.
What am I missing?

Disregard.
I changed all settings to use Built-in Audio Analog Stereo, realizing that I needed that in order to use a headset and Skype.
Audio clips from sites like youtube or vimeo stream fine, the only downside is that I do have to connect an audio cable to monitor, but I can live with that.
Sorry for pressing the panic button in haste.
Thank you.