This sounds like classic sparks sound that usually comes from the power cable attaching to the power supply. Try to push in the power cable and see if that helps the issue. Look with the help of a flashlight into the holes of the power supply power cable and the connector at the back of the PSU and see if you see the connectors having any sot on them or if they are clean. If they have sot that is a clear indication of sparks being generated usually cause either by a faulty socket or incorrectly seated cable. If the cable is bad then you need to get a new cable.
Video showing the phenomenon:
View: https://youtu.be/t5-QnNETzwQ?t=50