Hi! I have just brought a used Pioneer SC-LX73 and have had it running for a few days now. The other night I noticed a humming sound which after turning off all other equipment I have narrowed down to be coming from the receiver itself. It sounds a bit like a computer fan, it runs for about 20-30 seconds, then stops for 5-10 seconds then starts again. It doesn't start as soon as I turn it on, only after about 10 minutes of the receiver being used does it start. It is pretty loud - I first noticed it whilst watching tv at average volume sitting about 10 feet away. Is this type of noise usual (or usual to be that loud) for receiver like this? My old Denon 2310 didn't make this sort of sound (or at least wasn't noticeable). As it takes a while before it starts my first thought is it is due to heat. The tv rack it sits in is totally open front and back, there are 5cm between the top of the receiver and the shelf above, 20cm to the right but the front half of the left side is touching the leg of the stand. The top of the receiver is warm to touch after around 15-20 minutes. I understand it is incredibly difficult for someone to diagnose a 'humming' just from a description but I would appreciate any thoughts on whether this sounds normal or a possible fault as the seeds of panic are quickly starting to grow! Thanks!