Antec 1200 front panel audio, parasitic noise

ABBDVD

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Feb 23, 2010
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Hi everybody,
I got (some months ago) a Antec 1200 case for my 1st home built system. The system is running fine but I just noticed some days ago that the front panel audio connections have major parasitic noise (didn't use them so far). I searched a bit and read that the Antec 900 has the same problem too and that it is the ground at the front panel which leads combined from the 2 USB, 1 eSATA, a blue light (LED?, "flashing with the CPU usage") and the 2 audio connections to the case. The back audio works of course so i don't think it's my motherboard causing the problem. You do hear the music a bit, playing a song, but there's this noise when either the blue light is flashing (often) or if you have an USB device connected (you hear how for example an external hard drive is starting up and running). So i think it has to be the ground. I didn't try it out connecting an eSATA device.
Now I read that they just disconnect the ground from the audio or connect the ground to another better conducting spot on the case. I tried the latter but it didn't help. The other I don't know how to fix. I can't figure out how to open the front panel. It seems like it's one piece together with the whole top which is fixed to the case with rivets (i think). I possibly could somehow cut the ground away from the audio cables maybe, but the access is real small. Best picture i just found is the following. You can see the rivet and also how the cables go to the front above the disc drive. Those front bays are seperated to the top by a fixed metal plate (or at least it looks like this. Removing only the top front bay doesn't give me access.
I'm really thankful for any constructive advices, instructions help...
In the worst case I still can send the case back or I already thought about cutting somehow a whole out of the bottom of that metal plate seperating the front bays and the front panel back side but i don't know yet how i could do this.
Thanks a lot!

ABBDVD

100_0465jrm2.jpg


edit1: sorry, forgot to change it to a question and not a discussion and it doesn't let me change it. I am seeking an exact answer...
 

shovenose

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a few things:
1. yes some antec cases have that issue.
2. there is no such thing as a "cpu activity indication", the flashing light is a hard drive activity indicator.
3. i guess you could isolate the ground causing the parasitic noise???
 

ABBDVD

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2. yes, that's what i meant - you see i'm not a pro.
3. that's also the solution i'm having in mind, but i don't know how i can access front panel inside as i need to disconnect the ground cable between the audio and the other inlets (USB, eSATA and the HDD light from the case). just isolating the ground (disconnect to the case) won't do as the inlets are then still connected between each other.

any possible solutions how to fix this (mainly how to open front panel / other possibilities) are still appreciated.
 

Egg90

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Dec 18, 2010
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I've just fixed the same problem on my new Antec Two Hundred case, hopefully the front panel module is similar enough for you to do the same as I did.

18122010163.jpg


1: The first pic is after the job was finished.

2: Using a Stanley knife I cut away this section. You have to cut quite deep but as you see there is plastic moulding underneath so there is no issue with accidentally chopping wires. I wore a leather glove on my non cutting hand & glad I did as there were a couple of slips.
I could see through the white moulding that the only wire between the USB & audio seemed to be a yellow wire, which I thought was odd as in other threads people have talked about black or white wires.

3: So I cut another section from the bottom incase I could see any other wires that might go across the gap, but could see none. I shaved some of the white mouding away from both the USB & audio side & could see that the ends of the yellow wire were indeed soldered between the USB & audio connectors, and so must be the ground I was looking for. In the pic it looks dubious but the wire snaked around a bit inside the moulding.

4: After cutting back some more white moulding I managed to free a section of the wire & cut it.

5: I cut the wire a second time so there was no way it could reconnect & put some glue over the ends, before glueing the outer casing back on as in the 1st pic. The audio is now completely isolated from the rest, just using the mboard ground, so you can screw the front panel module's case ground back onto the case when refitting.

I really can't believe Antec have over-looked this for so long, I've read threads about it from 2008. I'm so pleased I managed to sort it out myself, I hope you can do the same.
 

ABBDVD

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How could you open your front panel? It looks like you could just "lift it out", or not? As my front panel is just one piece together with the case i can't open it this way :S

Is it possible to lift out the 2 audio female jacks? How without damaging them?
 

Egg90

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Ah right, on the Two Hundred you've got 3 clips inside the case down one side which releases the front to hinge on the other side once you've taken the cd drive out. Antec are usually great when it comes to dismantling thier kit, surely there's a way, but I can't help you on that sorry.
 

ABBDVD

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I tried to lift the female jacks out with a hook from the front. I couldn't lift it out. I guess there's a clip at the back side which detains me from pulling it out.
I made some pics to show my problem:

1st the duct to the back side of the front panel

2nd the duct from a bit further away. It's maybe not clearly visible but their is a fixed metal slab between the disk drive bay and the duct. (btw, the cable fixed to the case in the middle is the ground from the front panel...)

3rd the front.

4th my hook...


1st
2cijvo9.jpg

2nd
260wm4w.jpg

3rd
53s39w.jpg

4th
v745n5.jpg


Any help is appreciated.

Edit: resize pics