Question about RCA RS2640 CD Shelf System

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Strange buzzing noise

I hadn't touched my stereo since the day before yesterday. I turn it on today, and to my surprise, I get a strange buzzing noise. I change source input on the reciever, to try and see if maybe I had accidentally changed that. I switch through all of them, and still get the strange buzzing noise. I noticed that when I unplug the speakers, it disappears. When I plug them back in, it comes back. I even tried unplugging the thing and plugging it back in. I also tried messing around with the Bass and Treble and that wasn't the problem. It can be heard at any volume, even in mute. When it is on mute, the sound comes in and then comes out exactly like how the light on the display of the reciever does that says "Mute". I stripped the wires of the speakers and reattached them to see if that would work and that didn't help either. Also... When I change dimmer options, the buzzing sounds slightly different on each of the 3 different options. So if you guys could help me out with this, I'd appreciate it.

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Re: Strange buzzing noise

Sounds like a bad filter cap in the power supply.when you change dimmer switch the buzz changes slightly because of a different power sraw on the power supply. If you are not versed in electronic repair. Get an Estimate. Or if unit is old get yourself a new one. Good Luck

Posted on Jan 03, 2007

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Re: Strange buzzing noise

I took mine apart and found what I BELIEVE is a bad cap in C805/C806. (It appears to have kind of exploded for some was in a very warm operating enviroment). There is another in C512, but I think that one is just showing the residual internals of the above caps. I just ordered a pair of the 50v/100uf caps....I hope this fixes it! Ireally like this little stereo!

Posted on Jun 04, 2013

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