Sound effects from products

Towards the very end of this video is a click. I don't know how it's done but I believe it's done in one of 2 ways, either a very tiny mechanism built into the fasteners of this chair to make a click, or an electrical or magnetic method. With the sizes of microchips, transistors, capacitors, and other computer parts, people in the 60's or 80's would've had an extremely difficult time proving products are produced that can create sound effects to agitate the owner of the product.