Oh. Okay I was sloppy in my reading of the prior history. So I'll assume it wasn't plugged in the whole time you were waiting for the new PMU - which I assume is the power (connector) board.

Have you done a visual inspection of the logic board? Can you post some pictures? Actually, of both PMUs might also be helpful.

* But I still say what I'm seeing in that video is because of the battery. Otherwise plugging the adapter in would immediately cause that sound without the need for a soft boot. And the charge light is likely PMU or battery (probably latter).

Macdrone, what boards have 2 caps...?