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LM3875 kit troubleshooting

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I am having some issues with my amplifier and was wondering if I could get some advice. I have been getting some high frequency hums/noises when I hook it up to my computer. I plan to use my PC as my source. Hopefully this is not too much of an issue.

Unplugged from the PC-source, it is dead quiet. When I attach it to my Ipod Touch, it is also very quiet with only a small hum when I press my ear to the speaker. When I hook it up to my computer, the hum/noises is almost as loud as the music (it does not get louder if I adjust the volume through windows). I have no pot or volume control on the amp.

Using a single transformer and rectifier board to power two amplifier boards.

Currently I am using your power star ground configuration (I think):
Earth ground
PG+ from rectifier board
PG- from rectifier board
PG+ from both amplifier boards
PG- from both amplifier boards
CHG from both amplifier boards with a 8-10 Ohm resistor (although its shorted now, so I don't think the resistor is doing anything. I read somewhere that it was supposed to help...)

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I also read somewhere that you want to put a capacitor on each RCA connector. So I believe I have a 1 uF (not sure of value) under the heatshrink. If this is an issue I can verify by cutting the heatshrink.
 
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