Solved! ONKYO Receiver: Buzzing/hissing when plugging front speakers (5.1 setup)

[PLBoucher]

Hey guys, first time posting here and I'm hoping you'll be able to help me out!

I've had an ONKYO AV Receiver Model HT-R340 since 2008, connected to a 5.1 setup and never had any problems. However, I recently upgraded my home theater and ever since I reconnected everything, there is a buzzing/hissing coming from every speaker...

While troubleshooting the issue, I confirmed that every speaker individually works fine, but the buzzing starts when either the Front Right or Front Left speaker is introduced in the setup. Then, the buzzing is heard in every speaker.

Notice that I'm not trying it with an external input source yet: just connecting the 5.1 setup causes the noise.

While Googling the issue, the closest answer was possibly a ground loop. But it's particularly strange since the receiver is plugged in the same place as before. Even then, I tried it in a different room on another breaker and the issue persisted.

Any ideas or theories? I'm not really an audiophile, I just want my basic 5.1 setup to work like it did before so any help is appreciated! Thank you

 

[helpstar]

unplug power from the ONKYO, wait for about 5 seconds and plug in power again

which other parts did you connect and how (analogue or digital connections) to the Onkyo?

 

[PLBoucher]

unplug power from the ONKYO, wait for about 5 seconds and plug in power again

which other parts did you connect and how (analogue or digital connections) to the Onkyo?

I already unplugged it multiple times in multiple outlets.

There are no other parts connected right now, only the speakers. I am testing them using the receiver's calibration tone (white noise).

 

[helpstar]

which speakers are you using? How much impedance do these have

https://www.ch.onkyo.com/downloads/1/1/7/9/8/ONKYO_HT-R340_datasheet_EN.pdf

 

[americanaudiophile]

To clarify you have nothing connected but speaker wire and the receiver AC plug?
Does the noise occur only when you run the pink noise through the speaker or is audible all the time?
Maybe the noise generator is adding something it's not supposed to. Check how the speakers sound with a source. Try different surround modes too.

 

[PLBoucher]

To clarify you have nothing connected but speaker wire and the receiver AC plug?
Does the noise occur only when you run the pink noise through the speaker or is audible all the time?
Maybe the noise generator is adding something it's not supposed to. Check how the speakers sound with a source. Try different surround modes too.

Thanks for the reply!
• That's correct: only the speaker cables and the receiver are plugged in.
• The buzzing occurs as soon as the front speakers are connected, with or without pink noise.
• I tried it with a source and I alternated surround modes to no avail. However, with each switch of sound mode, you can hear a sort of pop sound.

 

[americanaudiophile]

With nothing but speakers connected to the receiver you can't have ground loop. The problem has to be internal to the receiver. At 12 years old it might be bad circuit board traces or the front channel amp circuits may have a problem. Not a DIY kind of repair. Might be time for a new AVR.

 

[PLBoucher]

With nothing but speakers connected to the receiver you can't have ground loop. The problem has to be internal to the receiver. At 12 years old it might be bad circuit board traces or the front channel amp circuits may have a problem. Not a DIY kind of repair. Might be time for a new AVR.

Thanks for the explanation! I had been leaning towards getting a new AVR, but I wanted to try every option beforehand, since it worked fine only a few weeks ago. Guess it's time!