The EQ rack is a four-corner post design with glass shelves. Open on all four sides and free-standing in the room behind the seats. Plenty of room above the equipment on each shelf too. I can't imagine any restrictions to ventilation.

I have a suspicion the problem is the actual temp sensor itself. The Aircom unit has an inlet temp display. It pulls air from the top of the AVR. I have not seen temps in excess of 80 deg. Seems to me that's not very hot for an AVR?