@Wayne-TP it has been connected to a COB LED lighting strip. I have emailed a video of the behaviour to support.forum@tp-link.com with the subject having the same title as this thread.

Experiencing similar issue to that described in this thread >> https://community.tp-link.com/en/home/forum/topic/610604 Plug in socket and it makes a capacitive squeeking type sound and the led...