Loud buzz on Raspberry Pi Audio Jack

Hi Nico!

That's a common problem, and not always easy to totally eliminate with wiring alone, but basically some current is flowing through wires with resistance (that are normally expected to be considered at 0V all along the wire), and that is causing the buzzing noise (which is likely at 60Hz).

It's a process of elimination, I'd first try swapping out the audio cable for a new one (maybe a different vendor one), to see if it makes a difference. Most audio cables are really poor (I make my own ones).

Aaah power! There's the clue I needed! Thank you!!

There aren't any special audio cables at play, but the speakers were plugged into a cheap little cube USB power adapter.

Switching that out for a different little charger cube made the noise disappear for a little while, but it came back at a lower level a few minutes later.

The other thing I had changed was that I replaced the cell-phone-charger-as-power-supply with a dedicated power supply that was recommended for the Raspberry Pi.

When I switched to using the cell charger again the noise went away, but the screen kept blanking out due to being underpowered.

I'll try a few more things to see. Might have to buy another new RPi power supply.

edit: Or maybe easier - try other speakers!

-Nico

Also along the line of power issues - Maybe I need to try a powered USB hub. Right now I have a USB wireless keyboard/mouse and the WiPi using power from the Pi ports, which is probably not ideal.

I have experienced similar issues. It came down to the audio cable.

Well dang, Shabaz just said that too, but there aren't any audio cables I can swap - it's directly attached to these cheap little speakers. I might have to find some better speakers.

You're using PC speaker type devices? What happens when you turn the power cord around inside the wall socket?

In my case, it was the connection between the audio jack on the pi and the audio plug. The pi's audio jack also contains the video connection. I attributed the buzz to the cheap audio cable's left or right inputs coming in contact with the video connection in the pi's av jack.

It could be the speakers but it's likely the plug is not making proper contact with the pi's av jack. Moving the plug around in the jack until the buzz stops is how I fixed on mine. This would be a temporary fix and might make the issue worse.

Yes, tried that. These are USB powered speakers meant for laptops I think.

It makes a difference which USB wall adapter I use though - some make it buzz a lot less than others.

That's a good point - I didn't realize that the pi includes video in that same jack. Maybe a headphones extension cable will help.