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Receiver humming momentarily when turned on

When I turn on my Receiver it hums through the speakers for about 3-4 mins. The humming level is constant regardless if I increase the volume or not, then the humming disappear. Thanks.

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Re: Receiver humming momentarily when turned on

I have solved thsi problem. The reseller suggested that probably a earthconnection was demaged and indeed that was the problem. by heating the earthconnections, specially the wired ones this problem disappeared.

Posted on Feb 02, 2008

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The subwoofer output on my Kenwood VR-606 has suddenly stopped working. I have tried the "setup" several times, turning the subwoofer off and back on. Also, when I first power up the system, it emits a low...

It sounds like the problem is not with your VR-606. If you hear a hum from the sub, the problem is more likely to be in the sub's built-in power amplifier. However, it is worth resetting the amplifier to factory presets. To do this, unplug the power cable from the mains supply and reconnect whilst holding down the power on/standby key. If the hum persists, connect any powered speaker to the sub-out socket, power on and listen for the hum. If no hum then suspect the powered sub amp. Turn the sub on with no connection to the Kenwood VR-606. If hum persists, the sub has a problem and will need to be replaced or repaired. By the way, you said there is a low frequency hum through the 'speakers' for about 30 mins. Is that all speakers or just the sub? Hope this helps.
Cheers, Don.

Jul 06, 2014 | Kenwood VR-606 Receiver

1 Answer

Major hummimng noise when sub is connected to receiver.

Is the hum in the receiver-attached speakers or the sub?

Self-powered sub?

How is the sub attached - RCA or speaker-level?

Disconnect the input(s) and see if it hums in the absence of an audio source. A bad audio cable shield or unwisely-routed audio cables will allow entrance of unwanted signals from external power sources, magnetic fields, even dimmer-controlled track lights. Sometimes, simply reversing the orientation of the ac power plug can eliminate humming.

If it hums with the sub attached, unplug the sub's power cord. Differences in AC ground potentials will generate hum across linked devices.

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Hello, my speakers hum for 10 to 30 seconds when i turn on my receiver. sometimes they do this even with sound coming from the system for up to 10 min. i tried changing the speakers. moving the power,...

i think ur unit deposits humidity . . try to clean it up with smooth paint brush over the boards and connectors . . better yet spray some contact cleaners i think this will do . . . otherwise resolder is needed . .

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Subwoofer hum from STR-DH800

That points pretty much to a bad shield on the cable. Have you tried another one? Another thing to try is to rotate the AC power cord on the sub (if it has one). Sorry, too lazy to look it up.

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1 Answer

60 cycle hum at the same constant level, even if you turn the volume up all the way, it does not get any louder. What might that be caused from? A bad ground solider joint maybe? The Balance (L&R)...

If the volume control does not effect the hum volume, then the hum is being introduced directly to the final amp section. Check for defective caps in the power supply for the amp section. This will be the nigher voltage supply usually 40V or more.


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2 Answers

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A couple of weeks after initial setup of my brand new Onkyo XT-SR606 receiver, I noticed a loud buzzing noise that starts up approximately 10 min after the receiver is turned on. The buzzing is definitely...

The "buzz" you hear is a power hum made by the power supply transformer. It's technically called "Lamination hum" caused by the revering of electrical current through the power supply transformer. In some cases the hum can vibrate the chassis causing other loose material to vibrate. If you can, go to your dealer and check to see if other units of this same type typically make a hum this loud, and if not, see if he can solve the problem for you.

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i think missing ground sheeld .
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can you poen the cover and check circuit board get wet anyhow,

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