Sound flickering between headphones and speakers and volume flickering when listening to something

I have an issue where on my ubuntu system my audio keeps flickering between headphones and speakers and when I listen to something the volume level is jumping between 100% and 50%.

I dual boot with Windows 10 and when I use Windows I don't get this issue. I just recently upgraded some hardware and before this I was not getting this issue.

In the sound settings panel the line out is flicking between line out and something else (too fast to really see) and the volume dips like the video. The flickering occurs all the time even without sound. If I kill all processes of pulseaudio it does stop for a bit. But then I can't hear any sound.

It can't be a problem with cable looseness as it works fine with windows. I've tried reinstalling pulseaudio. No luck.

Hopefully someone can help or advise where to look.