I got a weird message on my reciever this afternoon about it being too hot and that the current temp was around 141. I haven't had any problems prior to this. The side of the receiver is very hot. It's almost too hot to the touch. My receiver isn't in an enclosed area. I can't hear any noise at all coming from the inside when it is on and working properly. Is there a chance the fan could have gone out? How can I check the system temperature?