Computer not recognising disconnected headphones

So I have this odd issue with the computer I build a few months ago (it's always been there)
I've noticed people commenting that their computer does not recongnise when a headset is plugged in, but I have the opposite problem. I've set my headset as the default device, as I used to on my old PC, so that what should happen is that sound should play through my speakers when the headset is not plugged in, but through my headset when they are.
Problem is, my PC still thinks my headphones are plugged in even when they're not, as in I get the following screen in control panel even when the headset is disconnected:

And I'm really not sure how to fix this.

The Speakers are normally set as the Default Playback Device, not the Headphones.