WTB Sony STR 7055

[Rxonmymind]

Need your help. I have one which was fully recapped. Unfortunately once I received the unit there was this audible hum on the very efficient 104db speakers. 

We'll he went onto further replacing diods, reflowing the board etc. 

Looks as though we need another to see it to develops hum.

The unit doesn't have to be in great cosmetic shape or working for that matter as the tech will take both of them and see if he can make heads or tails of the hum. 

This is turning out to be one very expensive receiver.

Thanks

[ricktate]

Have made sure its the receiver ??  Try setting it up in a different room or use a different outlet. Did it hum at his shop?

I had a 7065 I bought new loved the looks and loved it but the right channel went out like 3 times I finally gave up on it. But I do wished I would have kept it now since I love the sound of the old HKs .  

  I also recently cleaned the controls on a HK 730 it developed a sizzle in left channel after. I was perplexed I did not touch anything and it was working fine. So I got a pencil and poked around on different resistors and transistors and was about to give up when one transistor made the sound worse. I had noticed it was pushed over touching a resistor. As soon as I pushed it back SILENCE wow that was awesome. Been working ever since.

[Osibisa]

Don't know if this helps but I once had a STR-AV1000 that developed a hum, and eventually found the culprit to be the ground between the main circuit board and the chassis. After backing out and retightening all the screws the hum disappeared.

[Rxonmymind]

Thanks guys. Yes it's definitely "hot". If you so much move your hand near it with the cover off it makes a humming sound. The tech has changed every diode, cap, resistor, transistor, moved around wires, reflowed some joints, rebuilt power supply 2x. 

Scratching head.