Question Click sounds when power supply connected

[msegmx]

When the power supply is connected (charging) my 6-year-old (Samsung) laptop makes clicking sounds (one per second), but only from time to time.
Every half hour or hour for 2-3 minutes it makes click-click-click noises.
The sound comes from the corner where the power cable goes in (the laptop's power button is on the other end).

Otherwise, the laptop is working fine.

Is there any part (like power supply inside the laptop) that could be replaced to make the sound disappear?
Or does the motherboard have to be replaced?

I'm worried that my laptop's motherboard might fry.
What should I do next to prevent this?

 

[hang-the-9]

I would first replace the charger and see if that fixes this.