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Humming noise in speakers?

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DaOld Man:
I plugged my new AV cables into my R-Pi frankenstein and I hear a humming noise in the tv speakers.
I noticed this with the camcorder cable I was using, so I dont think it is the cable.
I had to swap the red and yellow plugs at the tv because for some reason they are swapped on the pi.
Tried swapping the yellow and white but same problem.
Sounds like humming is on both channels.
HDMI into tv has no noticeable hum.
Anyone else experience this?

Slippyblade:
Audio on the Pi sucks almost universally.  One of the most effective things is swap out your power supply.  If you have one with the weird block in-the line (ferrite core or something like that) that tends to make a big difference.  Ground leakage seems to be a big issue.

As far as the A/V cords, there are a couple different pinouts used on this connection.  This article (http://www.raspberrypi-spy.co.uk/2014/07/raspberry-pi-model-b-3-5mm-audiovideo-jack/) explains it well.

DaOld Man:
Thanks Slippy, looks like I just need to swap yellow and red. White is left audio.
I tried reversing the polarity of the ac power coming into the power supply and it helped considerable.
There is still a slight hum when on emulation station menu, but it goes away as far as I can tell, when I start a game.
I am 99% sure I kept the polarity straight all the way from power plug to the prongs on the power supply, but I could have swapped hot and neutral some where.
This may be an annoyance if using a non polarized outlet.
I may look into a 60 HZ filter for the DC output of the power supply.

DaOld Man:
Not too sure about the swapping of the 120 VAC wires. I might have just turned down the TV.
I will see if I have another 5 volt power supply, this one does not have the ferrite filter in the DC line.
I may have a ferrite core I can try.
I plan to do more research on this problem. If anyone else has solved it, I appreciate you sharing.

behrmr:
You could always try a ground loop isolator

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