What model reciever is it? Also how long does it take to get to this extremely hot state. A friend of mine has one and his doesnt get extremely hot, but it certinly does create a good bit of heat. Onkyo's generally create much more heat than other brands. They even recommend more clearence space above it than other recievers, I would check the manual for the clearence space required and as long as you follow it you should be fine. I wouldn't worry too much about it unless it starts acting up or creating a strange smell.
