We've been working with the BlsckMagic Design ATEM Mini Pro and ISO since they were each released and like many others, were frustrated by the excess heat and totally inadequate stock passive cooling mechanisms of these devices. Our first efforts were around creating stands that would elevate the device off the desk, facilitating some additional airflow under the units, but more recently, we discovered a significantly superior solution, beautifully augmenting the stands, and perfectly integrating with them.
We Came across this add-on heatsink solution marketed for use with iPads but fount it to be a perfect complement to the ATEM Mini line of Live Video Switchers.
The cooler mounts beautifully using supplied thermally conductive adhesive, to the back of the ATEM Mini when it's mounted in either one of the many models of 3D Printed stands, including our design, and in the event you elect not to purchase or print one of the custom ATEM stands, the cooler ships with a wire stand, as a functional - albeit less elegant - solution.
Regardless of the mounting solution you choose, this supplemental heatsink, with nearly silent fans enhances heat dissipation to the point where the ATEM is cool to the touch - a massive improvement over the default condition where as some have said, you might be able to fry an egg on the ATEM Switcher.