For years I’ve had fans in the back of the audio cabinet to keep my stereo stuff cool. Even modern equipment generates a lot of heat, esp the Receiver or any Amps you have.
When I got this audio cabinet about 8 years ago I put 3 fans in it. I got the best fans that I could find to reduce the hum that fans all make – Vantec Stealth 5″, and a Vantec Stealth 3″ for the center bay. There is a small transformer hooked up to the Aux power of the receiver so that the fans turn on whenever the receiver is on.