Electrical interference with microwave

[ban-all-sheds]

You could do that.

Or you could answer this:

Does it have some kind of fibrous cover over an aperture where the microwaves emerge?

 

[aptsys]

You could do that.

Or you could answer this:

Not sure if you played the video, but the sounds were present even when it was not microwaving anything

 

[ban-all-sheds]

I did play it, but I didn't notice that.

If it's doing that when not running it is probably easy to diagnose and fix.