Headphones crackle on the laptop?

The background noise that arises when the laptop is working is very loud to hear with my headphones.

I have already tried to find a solution in the Soundmixer, but even if I turn off all audio outputs and the microphone, the noise is still there.

Maybe someone has a similar problem and a solution for me?

UPDATE: I found out that the crackle is only there when the power adapter is connected to the laptop. (even if the laptop is off and the power adapter is on, the headphones crackle) how can I get rid of the noise?

Maybe the headphones are broken? Dust in the connection or headphone plug broken?

I found out that the crackling is only there when the power adapter is connected to the laptop.
Right. The reason is the grounding of the power supply.

Thank you. Is there a way to fix it?