LOUD Humming- HK AVR510

[TDrag]

Recently my Harman Kardon AVR510 receiver started "humming" pretty badly... actually the sound is not from the unit, but can be heard in every speaker, even with the volume completely down. I use monster cable wires, and have it connected to B&W Nautilus speakers. I have checked the surge supressor, and have even tried plugging the receiver directly into the wall. Have tried different outlets. I have removed every single connection to the back of the receiver and tried running on FM, but still have the problem. I have disconnected the speakers one by one, and it still does it no matter how many or which speaker is connected. This only started recently. The sound goes away for a split second when I switch inputs, and then comes right back. Doesn't matter if it is digital or analog input either. I guess I will have to take it for repair, but thought I would inquire here first to see if I am missing anything, or to see if HKs are known for this... any input would be appreciated. thanks

[radio66]

try using a 3 prong addapter this will emiminate a bad ground in your home wireing,this worked for me.

[afpyro22]

I have the same issue. I have the Harman Kardon AVI200. Recently it started making a loud buzzing noise, regardless of inputs or volume. I had everything disconnected except the speaker wire and one speaker and it still occurred. I did not try connecting it into a different power source. I just dropped it off at a local repair shop, but haven't received word back on the status. I'm interested to know if you have resolved the issue, or if anyone else has a suggestion as to the problem.

[audphile1]

If you have cable tv, try disconnecting the antenna cable from your system at first point of entry. If that will get rid of the noise, then you need Mondial MAGIC box, which is a ground loop eliminator. Let me know how it turns out.