The rapid movement of an object (such as the speaker in my clock) throws surrounding air molecules into a frenzy. (discovermagazine.com)
For example, the heating and cooling controls are integrated into rings surrounding the air ducts. (speedsportlife.com)
The enclosures are designed to minimise radiant heat penetration into the enclosure from its surrounds, so the major impact of such static heating sources is going to be from heating surrounding air which may then pass through the enclosure. (skepticalscience.com)