[SOLVED] How am I playing sound through my headphones while they're turned off?

[Name1]

Hello
Recently bought the sony wh-1000XM3 headphones that I have wired to my windows machine though an AUX cable. Today I forgot to turn them on, but somehow they're still playing the sound from my pc. How can that be?
Is this some sort of feature of the headphone or due to the aux wiring?

 

[Phillip Corcoran]

From the Help Guide:

Making the connections >> Using the supplied headphone cable >>

"You can listen to music even if the headset is turned off"

https://helpguide.sony.net/mdr/wh1000xm3/v1/en/contents/TP0001703069.html